

It’s more than just FOSS users. It’s “The Internet” in general. At least two of the modding scenes I’ve been in have had multiple developers (and artists and translators) just quit due to their users aggressively complaining about the stuff they give away for free.
Of course, it doesn’t get that much better when people have to pay for things – ask customer service representatives how much toxicity they see from unsatisfied customers.
Self-hosted GitLab is what GNOME and Debian chose to do.
I still use the main GitLab for most things.
https://repo.or.cz/ provides just git hosting.
It’s also relatively easy to just self-host Git, though permissions can be wonky, at least last time I tried.
I can’t recommend Darcs. Luckily I don’t see MS (or any other corp) being able to take over core Git development. I really should try Pijul again, but least time I played with it, the history/branch visualization (which you can do without, but I really like to have) was actually still worse than Darcs.