I still use it. For that which I engage, or who I engage with, it hasn't changed for me. Almost 100% for metal bands. Tours, album releases. We have a pretty cool metal community going. People I've been speaking with for many years now.
Leaving a platform you don't like, or the reasons you don't like it, isn't "common sense".
Never underestimate the network effect and how reluctant people are to move to another social network. The masses just follow the crowd, so every big account moving out from there helps take more users away.
It's a shame I haven't seen more YouTubers leaving X, they all seem to use it to talk about whatever they do. Not that I watch a lot of YouTube these days but my family does, younger ones especially watch those minecraft SMP types. Its arguably the most toxic social media but "everyone's on there".