Cuz the comments throught Lemmy/Piefed seems to indicate that literally every user on here is a FOSS/Dencentralization Purist and has 100% abandoned mainstream platforms.
I wonder if this is actually true or just a small minority of users being overrepresented.


No, not anymore. I also think about sun setting my other account on the microblogverse (never used twitter but started using mastodon because its foss weirdly enough).
I did use Reddit the most of all mainstream platforms but stopped way before the whole API debacle as I grew tired of the community recycling old jokes and the circle jerk.