> I see reviewing and accepting a PR is a question of trust

I think that's backwards, at least as far as accepting a PR. Better that all code is reviewed as if it is probably a carefully thought out Trojan horse from a dedicated enemy until proven otherwise.

I think this is actually a healthy stance. If you want to maintain patches against a project, just maintain a fork the project and if I want to pull in your changes I will. No direct submissions accepted is not the worst policy I think