Like I get there are several reasons people remain. It just feels kinda weird to listen to a podcaster or youtuber go off on twittter, yet they still use twitter exclusively.
When people dont wanna switch to madtodon because its another app and too lazy to set it up but everyone suddenly starts using threads when facebook releases it.
I'm glad it did. Imagine: People keep complaining about Xitter, refuse to use Mastodon, then suddenly all migrate to Meta because new platform hype. This almost actually happened and I think the only reasons it didn't is that Threads is inaccessible in Europe and from what I've heard the app was crap.
Too many people are just so basic they won't even consider trying anything but "mainstream". If Lemmy or Mastodon became mainstream platforms, you can bet they would come in masses because "there's where everyone's at."