Important Open Source projects should not use GitHub
unixsheikh.com
unixsheikh.com
Given the current situation, contrary to what the author affirms, important open source project that wish to attract contributors should probably use Github.
If I'm the maintainer of a project of course I would have backups (even if I trust Microsoft because GitHub could be hacked). And for important open source projects there are probably many people who have a copy of the repo.
Also, based on the way git works I’m certain there are dozens of backup copies. But I know I keep specific copies as well. It’s super easy. It’s git.