I hardly get any contributions, questions, etc even though I have published them on GitHub (although some people do watch and/or star them, but I don't really care much how many stars it has).
I think you can disable issues but not pull requests, as far as I know.
It might be helpful to allow to disable pull requests too, and possibly to hide how many stars/watchers there are and hide the list of forks (people could still star, watch, and/or fork the repository, but they would not be listed on that repository if the display of those features are disabled).
Whether or not GitHub accepts these ideas, it can be an idea that other services (e.g. Codeberg) can consider adding such options if they want to do (as well as other things).