Did you also try Forgejo? If so, what are the differences between the two? I didn't even know GitLab had a self-hosted option. I assume it's probably better for Enterprise-grade projects, and dealing with CI/CD, actions, etc. But for smaller projects that just have issues and PRs and minor test suites, I assume Forgejo is the better lightweight option.
Yeah I tried hosting forgejo and the first issue I found was that it was crashing some of the time with our large monorepo and getting actions/runners up and running was proving time consuming; I really did like how lightweight it was, monolith wise. gitlab has a lot more architecture behind it but the documentation is very good at describing how you should configure it for your needs.
I think Forgejo would work fine for smaller projects and teams. We really wanted to stop having to worry about GitHub going and not being able to do CD as well as get away from a lot of the action zero-days happening.
And yes, it's self-hosted and free! You can run a reference implementation pretty easily with non-production components (i.e. they won't backup or scale well).