Obligatory don't put all your eggs in one basket.

There's countless alternative git forges, self-hosted or not... I suggest people use multiple for redundancy, even if they are just read-only backups.

Maybe it would be nice if git had a way to add multiple repo URLs for the same remote.

It exists apparently: https://stackoverflow.com/questions/849308/how-can-i-pull-push-from-multiple-remote-locations