Mostly to Lemmy instances

tildes.net, lobste.rs, ycombinator and lemmy.world are some of them to the best of my knowledge. Of course, a big number is still battling it out on reddit itself, some are pushing the mods to open up the dark subs while others are joining alternative subs and having those discussions anyway.

Don't try lemmy just yet though, I think it is excruciating under too many uers, the platform isn't entirely bug free. Writing decentralized social network is complicated and takes time.