My understanding is that some users dislike reddit but very much like their specific small communities in it. They want to maintain the value of their community without relying on Reddit to host the content, so they are trying to migrate to places like the Fediverse. With that being said, I only support that for smaller subs with their own established community culture. Also, transition is hard so some people want a few familiar landmarks while navigating this new land.

Reddit: Constantly getting worse. Lemmy: Under active development and (hopefully) improving over time.

I know which community I want to invest my time in.