Why should a maintainer care about keeping PR count as a signal of developer status? A good quality contribution is a good quality contribution. You only have a responsibility to your own users, keeping out bad code from your repo while accepting as much good code as you can without getting overworked. You don't have to look after other people status games.

If you judge first time contributors on accepted PRs that's as dumb as doing it based on their activity. It tells you nothing about quality. You're the stupid one for assuming all maintainers are as strict as you are.