even the worst corporations are on the right side of something from time

Well, corporations (best and worst) are always on their own side… which sometimes happens to be the same as their customers’ :)

With something so niche as pico-8, you are probably better off just biting the bullet… In your shoes I’d investigate if there are viable FOSS alternatives and, failing that, just fork the 15USD the developer of PICO-8 asks for.

I have four accounts on the four instances that host communities I am interested in.

It’s a mild pain and definitely not what we were promised, but I guess that’s the only way federation can really work in practice (especially considering when an instance is blocked user on the blocker side just continue to see it frozen in time, with no warning as to what’s going on)