I've had the opposite experience, with lemmy instances always down or not federating correctly (like, blahaj.zone currently 502ing), and kbin generally running smoothly.
I'm also pretty sure the error on the right is what you get when the issue is with the other instance you're trying to interact with, not with kbin, but that's my own deduction, not something I actually know lol

Fair. I probably just encounter way more errors cause I use kbin way more than I probably should lol. The error on the right though has been particularly nasty on this account for me. Posting content as a link seems to be the only way I can get content to appear.