Twitter is defined entirely by what is followed, you can stay completely out of the toxic far right stuff and block those that don’t know where they are. There are still plenty of sub communities there that exist no where else and you can control your feed better than Lemmy and other forum like systems. Twitter overall is declinimg but it’s not the full picture because what is happening doesn’t impact lots of people who use the platform that much.
Having now flooded the internet with bad AI content not surprisingly its now eating itself. Numerous projects that aren’t AI are suffering too as the quality of text reduces.