I made a lot of good and close friends online in my teens and early 20s through my minecraft communities. They were people I stayed in contact with for years (some were close enough that we'd be texting most of the day), we were part of each others lives growing from teens, to seeing some of them getting married, getting jobs and having kids. Some of them I met in person, we traveled together, and in every respect they were true friends. Distance slowly crept in though and the fact that they lived in different countries and were living different lives meant we just didn't stay in sync at a certain point.
Initially what made those friendships work was the fact that we always had a shared project together (the minecraft server), that was a space we met daily. Plus, in a minecraft chat, its ephemeral, its not logged or archived like a forum, you can joke and say dumb things and be yourself and no one will care in a week; and that's important for making friends.
As I've gotten older (im in my early 30s now), I find that online relationships I had as a teen just don't give me what I need any more. I don't want to be on a game every day, I don't want to invest time into a friend I might never actually meet, or who might vanish the way online people do. I want my friendships now to be more direct. When I hang out with a friend, I want to actually be able to get a coffee with them, and talk in person, and have them understand where we are both at in life, and feel we have a future in each others lives.
I bring all that up, because I think a lot of people in the indie web are in their late 20s to early 30s and its worth acknowledging that what you want out of a friendship changes as you get older and the web may simply not be able to provide it.
I really enjoy interacting with people on ML for example, I enjoy offering knowledge and sharing ideas and joking with people (and sometimes debating too), but I've never really looked to make close friends here, and I don't think I could even if I wanted to.
That's fine though, if the web revival has anything to offer, its that the web is a wonderful thing, but it should not be everything, and it should not necessarily be a place for finding close friendships all of your life; it can certainly help connect people, and it can be a great shared interest and passion to have with a friend, but I think good friendships start where the web runs out