You’re most likely not looking to selfhost plain git but more something like GitHub (Web frontend, administrative tools etc.). I use Forgejo (installation guide) for that and am quiet happy with it. Its more lightweight then e.g. GitLab.
I’m currently trying out OpenCloud (I think a fork of OwnCloud, where Nextcloud was forked from). It’s working fine on PC where I had syncing issues with Nexcloud as well. I also host a syncthing server for the few things I really want to have in sync for all my devices (mostly my Obsidian Vault). It’s been really reliable, especially compared to other solutions I tried out
How does this compare to tuwunel?
I would say its common in Germany as well