Git is not a search / discovery platform. Publish the same git repository to several platforms and you can collaborate in a distributed and decentralized way through each of those platforms.

Nothing stops you from publishing the same project to both github and gitlab.

No, but it makes it more difficult.

Why would a project that's already happily working with the Github ecosystem want to also have to support publishing to a platform that doesn't block China? Lots more work on project maintainers.

>Git is not a search / discovery platform

Yes, that's very much my point - GitHub is.

To suggest that GitHub is somehow the same thing as git, but centralized (=> bad) is missing 99% of the value GitHub offers.

Answer that question and you might have a startup company...

My vote is for IRC

IRC is definitely not a good way of searching/discovering anything.

That's just your experience. Neither is github from mine.

Mailing lists?