Thanks for trying that! Inconsistencies like that are probably why comments don't sync correctly, right? For instance, on this thread (https://kbin.social/m/kbinMeta/t/10635/Today-at-23-00-GMT-there-will-be-a-30-minute-technical) there are 13 comments, whereas on the corresponding thread in Lemmy (https://lemmy.ml/post/1194271) only 3 comments show up.

That's possible! I thought that could be the issue. I was a bit confused because it looks like "posts" are put in the "microblog" category on kbin which I thought loosely corresponds to Mastadon-style posts. But maybe I'm wrong...