Now that there are some replies, I feel like I can give my own opinion without it setting a specific tone for all the replies!

Everything is wrapped up in what our definitions for "influencer" are, so I'll also be unpacking some of what that means for me here.
What do you generally think of online influencers?
My general thought of an influencer is that they're just people, too, and whether I think well or ill of them depends on the person, including what exactly they want to influence people toward.
What do you believe their role has been when it comes to the evolution of people's engagement with the Web?
Once upon a time, the landscape was a bunch of DIY, people taking videos of their cats doing silly things or adding everyone they could on MySpace. The "and you can, too" attitude of the whole thing demonstrated freedom in terms of the creations you could share, and there wasn't really a landscape of trends that people would be compelled to follow. If people followed a trend, it was generally because they simply wanted to, not because there was an incentive. In that era,
what would become the "influencer" was a generally positive direction for the Web because it showed people the many ways that they, too, can express themselves and contribute a verse, without worries of it risking anything in their future.
There's a whole history around what exactly happened with that over the course of the 2010s, but there's basically now a landscape where content creation is mostly constrained to specific platforms, those platforms themselves constrain content visibility to please advertisers making demands, they pass those constraints onto whichever creators' work is visible to people, and it makes the next people (the influenced) think inside the box of those constraints. This makes people believe that influencing others means today what "selling out" meant early last decade, because content platforms will display influencers who both garner the most attention and please those platforms' interpretations of advertiser constraints. If that's the only content you see, then it may be the only content that you see as being possible, so it becomes a straightforward conclusion from "I want to share lots of stuff online" to "I want to be an influencer," even though those of us outside know that that's not true. Now, even people who wouldn't make content without the money did often have some vision that wound up being adulterated more because of advertiser constraints than anything. It's why even for a while after people knew it made money, influencers still made risky & freeform content, right up until advertisers started pulling funding to leverage demands on what content their ads showed up on. Those who make content regardless of these constraints are still out there, though, just mostly invisible, and for those who have a genuine message they believe is important, they know that the most effective method is to play the game. So now, unless you're an active independent participant in curating your own experience of the Web, a specific experience of the Web will be fed to you, one whose face is a certain highly visible kind of influencer but whose rules are set by the advertiser, with those rules enforced by the platform.
That's the influencer's most visible role in the engagement people have with the Web, and
though the mainstream role of the influencer is more of something that's imposed on them by platforms & advertisers, that role's effect is currently generally negative because it keeps people trapped in those constraints of what they think the Web can be, in what online creation can mean, therefore keeping people from expressing themselves freely (or even knowing how

). Over time, this keeps others from knowing how freely they can also express themselves or sometimes even the things that they can enjoy.
However, that type of influencer doesn't encompass all of what an influencer can be. An influencer can also rebel against this system, or inspire others to create, or educate people, or simply create while making no effort to influence, or even be entirely unaware of their influence. The general role of the influencer is to influence, and taken holistically, the online influencer's role is to canonize where Web culture will go in the future.
Are you particularly invested in any online influencers?
If they have a consistent message that I can get behind or something useful that they bring to the world, I'd say I enjoy them being there. I can get behind the message of
independent repair advocate Louis Rossmann (whose
latest video is about sticking it to the bloat in the online ad insutry), and I do enjoy Michael Stevens & Jake Roper from
VSauce. However, I wouldn't say I'm "invested" in them any more than an artist who made a drawing I like. For me, that's particularly invested as far as influencers go.
If an influencer came here, do you think this could be a welcoming place for them?
Yes. Influencers are just people. However, I imagine some people would shake a little around it, like if a celebrity joined their friend group. Some (or even most) of the people might be oblivious to it, and others might be waiting for the opportunity to confront them on their status, at least until they've been around long enough to make clear that they're just regular people.
People here might think more highly of them if they "walk the walk," coming in with their own non-corporate websites or other experimental / DIY noncommercial artistic projects. However, it could go very sour if they tried posting about or using Melonland as a way to advertise themselves or their products, or if they tried leveraging their influence for special treatment. Though, it could also go very sweet if they taught their audience ways to engage with & create on the independent Web, or if they created or bankrolled independent Web projects (like Neocities) that helped people express themselves outside of the advertiser-controlled landscape. Depending on the influencer, them being welcomed here is very much possible!
Do you believe that becoming an influencer always sacrifices some authenticity?
Being an influencer in itself doesn't sacrifice your uncoerced self-expression, as you sometimes gain influence creating online content without actually having the goal of influence. Sometimes, you're just keeping a record for yourself, or you want something to exist on the Web that doesn't exist yet. A lot of us do both of these things already, but influencing means what it means: influencing others. Some people (or a lot of people, actually) change their behavior when they become aware that they're being watched. It's called
the Hawthorne effect, and different people are affected by it in different ways & to different degrees. Though it's psychological in nature, I still believe it can count as clouding a person's authentic expression, depending on how it manifests.
If you're a photographer for a local newspaper & people keep posing for the camera when you just want a candid shot, it can certainly feel like the camera makes people inauthentic, but there are also people who do just continue doing what they're doing. Many people are very affected by the spotlight, but there are a few who can maintain their candor. I imagine that once someone is an influencer, it becomes a more or less permanent spotlight, and how it affects their authenticity depends on the person. They may also generally gain mental fortitude against the spotlight as they get older, but the online landscape hasn't been around long enough to conclusively extend that theory to online influencers.
Since the role of online creators has changed a lot in the recent decades, do you see a future where influencers may create freeform as they did in the past, back before people even knew it was a potential career path?
I do, but it must be worked toward by people challenging the mainstream ecosystem through tangible alternatives. I feel we're currently in an era that invites many futures for the online influencer.
In the past couple of months, people have been making mass movements from the most popular services to some less popular ones. People have gone from Twitter to BlueSky and from TikTok to RedNote. These are each due to different events, but they show that the audiences are faithless toward the platforms themselves. And the platform is a necessary ingredient to the coercive landscape surrounding influencers. If you change the platform, you change the rules. There are many wrong ways to do this, as shown by "free speech" platforms that were quickly overrun by people other platforms didn't want, but there are also more correct ways, especially with platforms that center around its users all being creators, like Neocities, Pixiv, or AO3. With the churn going on between platforms, who's to say a new creator landscape with different rules won't pop up and challenge the demands of advertisers, or might even be in-applicable for such advertiser demands because it's just an aggregator instead of being a host?

It may happen later rather than sooner, but I do see an eventual future where creative control can come back to the people by simply providing a more democratizable & independently indexable service (or even just format) for creating with.
If someone wanted to encourage a lot of people to think about the things they value or some important thing that exists, how might they accomplish spreading that message without influencer marketing tactics? Would you consider there to be alternatives for what it accomplishes, or is it all-encompassing for that?
I've noticed the answers for this question don't really get at how exactly to spread the message. Eliminating the system around it doesn't get the word out about your message, and doing things publicly with the door open sneaks in that,
somehow, people can see it.
Well, that "somehow" has already happened, because we're all here. We found this place.

Melonland is an example of non-influencer messaging. To simply mention it where it's relevant is a fair enough tactic to get your message out, and in some ways, it's more effective. If the message resonates with people, they go on to share it themselves, without any imperative or incentive aside from the message itself. Sure, it won't be for everyone; it's not trying to be. And that's where you want your message: with the people who want it.
But if you really want to get your message out far and wide, what do you do? You can try viral marketing tactics. Going to conventions & concerts and leaving handwritten sticky notes in your wake can get a few people curious from far & wide. But if your message is really that important for everyone to know, then that's what a traditional ad service is for. You pay 'em, they market it. It was there before influencers, and it's there now. Though often, a message isn't that type of important, where I would want to bother a bunch of people who aren't interested in it...
Influencer-style marketing definitely isn't all-encompassing. It's just a type of toolset or service or project that's up for rent. And a project is only as good or as bad as the people leveraging it & carrying it out.
So, overall, neutral, but in the chaotic sense where it's a mix of the good & the bad.