It’s entirely possible that my timing was just bad for Mastodon and good for Lemmy. The fact that I could jump on Boost and have an extremely familiar experience was a big plus. Bluesky was more similar in terms of migration experience to Lemmy than Mastodon was.
The other issue is that in a forum site you follow topics, where on a microblog site you follow people. The topics are here on Lemmy (to some extent), even if the people aren’t, but I don’t really care about the individual contributors as much. The people I wanted to follow for microblogging went to Bluesky, and that matters a lot more there.
Your initial post and response here describe my position as well.
Simply put, to follow individuals, you have to be where those individuals are. On Lemmy here in looking for topics and discussion, those are much easier to decentralize.