Codeberg and Sourcehut are doing it for free, for open source. Corporate probably won't ever move off Github, because they need the prestige of using Github - the actual service quality is completely irrelevant. This is an aspect of the enshittocene epoch - I repeat, quality is irrelevant to corporates.
Sourcehut isn't free and has weird UX, Codeberg is free but has poor performance and weirdly over-moderates discussions. I know corporate will always suck, I'm just talking about having something that approximates the "old GitHub" for personal/professional use
The SourceHut UI looks weird compared to commercial offerings, but every time I use it I am pleasantly surprised how fast it is and how little clutter there is.
