People tend to focus a bit to much on the Git part of Github. Git is already relatively fine. It's nice to have a web view into the repo, users can just clone the repo, but many seems hesitant to do so as if it's some major operation (it can be for large repos, but normally it's not).

The tricky part is the bugtracker and pull-requests. I don't really know how I feel about the Github issue tracker. In theory it's a good way for a community to report and manage bugs, but it's also what's driving maintainers crazy. Previously, in the olden days, you'd send an email to a mailing list and maybe get a reply, maybe got told to show up with a patch or bugger off.

To some extend Github removed to much friction, and while quick drive by patches can be great, they don't build much community.

it is - but dealing with code involves a lot more than just git.

tangled distributes the rest of the stack - issues, comments, pulls, stars, etc.