It is if you don't care about any of the other things that Git brings to the table.
I fail to see what `git rebase` has to do with issue trackers, project boards, wikis, repository notifications, or any of the other things that GitHub does. I use git forges as well as `git rebase`. Neither of these things precludes the other.
I find them useful, as do many others. They can do many things that commit messages obviously can't.
You can technically coordinate many of the other things through external tools like email, but email sucks, and there is real value to having them all in one place.
Obviously, I'd rather have all these things part of the repo itself, like with Fossil. What's what Radicle is trying to do, it looks like.
I fail to see what `git rebase` has to do with issue trackers, project boards, wikis, repository notifications, or any of the other things that GitHub does. I use git forges as well as `git rebase`. Neither of these things precludes the other.