I think that most experienced open source maintainers would probably understand this approach, and it's definitely something I've considered making explicit rat

I think that most experienced open source maintainers would probably understand this approach, and it's definitely something I've considered making explicit rather than implicit. I don't find rejecting people too difficult or mentally taxing, though, personally, so I haven't felt the need to reach for an explicit policy. I can point to this as an example, at least, if I ever do. I found your wording to be sufficiently explanatory. Good luck with the project.