PRs are not optional: there is no way to disable them on GitHub. I can't be sure that this is intentional, but it certainly works out well for them that this is one of many properties which make it quite difficult to migrate away from the platform.
Yeah, that's actually what we've done on the Zig GitHub repository. However, it doesn't stop pushes to existing PRs, which isn't ideal; and, yes, it's quite hard to escape the conclusion that there being no "until I turn it back on" option is intentional.
You can close them and limit discussion to contributors I guess? Not ideal but at least they wouldn’t appear in the pull requests tab.
Alternatively you can use a bot or a GitHub Action to automatically change the description and title of the pull request to something like “[PRs are not allowed and deleted automatically]”. But yeah not a perfect solution either…
It's completely intentional, and goes back to when GitHub was founded. GitHub was intended as a collaborative software development platform, not "look but don't touch".
I suppose you can fork a repository if you want to collaborate with others though. Reviewing pull requests and engaging with a community is a lot of work and has possible legal ramifications; in many cases it’s faster to just do things yourself. Some teams/companies deliberately refuse outside contributions for this reason.
