For me pull request model is much more natural than mailing lists and patches. It doesn't matter at all if its GitHub, GitLab or (my personal preference as it's lightweight, open source and easy to use) Gitea (interestingly it's not present in comparison on https://forgeperf.org). I don't even know how to make PR on sourcehut and can't find any tutorial.
Of course I will try to learn in order to help org but the entry barrier is much higher than for Git(Lab/Hub/ea).
EDIT: I just found orgmode code on Gogs here: https://code.orgmode.org/bzg/org-mode
That's great! I'll register and try to help soon! Mabye it should be more visible and linked in docs (I'll... make a PR I suppose? :)