Open mobile app support

Ad free (depending on the app and instance, but its pretty easy to get Lemmy without ads)

No CEO to make whacky, unpopular decisions without clear purpose or recourse

No shareholders whose priorities will always take precedence over the users

There’s also something to be said for being part of a smaller community

Of course any and all problems can occur in microcosm within a particular instance or community, but it’s trivial to just block that instance/community. As for brigading, bullying, and harassment, Lemmy offers no solutions to human nature, unfortunately.