GitHub doesn't allow a project owner to block PRs. You can spam any public project with PRs. And people use it to file issues where the issue tracker is not public. Lets improve on that in NIP34 💪
Dumping some nip34 thoughts: 1) maintainer opt-in feature 2) allow list or WoT based 3) must be clearly communicated to potential contributors in clients 4) could specify rules that could be implemented in a ci environment via a DVM. Eg. Must add or update tests, or must pass standard ci pipelines. A DVM could run the checker against the PR/patch set and respond with a specific comment before the PR gets shown publicly and to the maintainers.