I mean it’s fair to say that there have been many performance issues as most of the federations were not prepared for the mass influx of people, and for someone literally brand new and without context it’s hard to differentiate between temporary performance issues and fundamental flaws. I agree that all the bellyaching is laughably naive about how quickly websites and services come together and evolve, but we can’t pretend that the growing pains haven’t happened.
I get the impression that Mastodon and kbin.social are technically interoperable with Lemmy, but not very well.