Automattic's CEO actually answered a bunch of Tumblr-related asks on his blog recently in light of this stuff. I thought some of the answers were interesting, especially the breakdown of Tumblr's subscriptions:
"Out of the 11.5M monthly active users of Tumblr, only about 27k have subscribed, or about 0.2%. If that were 10 or 20% we could run the site forever."
I've seen some people say "Tumblr should go open source!" which is frankly... very silly. Open source isn't a magical fix-all button and it won't help the core of this issue, which is that Tumblr is expensive to run and operate, like any supermassive website :(
I don't think moving to a skeleton crew is the end of the world but it can very much be a writing on the wall type of situation, especially because as shevek said I imagine less and less people are willing to stake millions on turning around Tumblr after seeing so many people fail to right the ship. I know not all the changes were liked but to see the lowkey subscription services flop after a lot of people always rally around the idea of them bodes really poorly for anyone looking to pick it up.
A former employee said this in another post:
"27k people subscribed to ad-free means around a million per year. This is after over a year of growth. That's less than one month of purely infrastructure costs, not even having staff wages into account. The badges and rest of the sales are doing significantly less than that."
That's a lot of money for any company to be hemorrhaging every month. Who wants to take on a debt like this for a ship that's proven unprofitable? :(
I don't have much of a horse in this race as I stopped using Tumblr years ago. Like in 2015 or 2016 I think? But it still sucks.