As a maintainer, I regularly review the open PRs looking to close stale ones. But most of them are good ideas that just need a client sponsor or two to go through.
Discussion
Absolutely. Closed ones can easily be found and re-opened if there's interest. This is just one of those things that turns into a red flag after looking at tons of repos.
NIPs, like all open source efforts, are a product of a healthy community so everything should work toward supporting the vibrance and diversity of that community.
Yes, that's true. I would hope a new cobtributor would not start by writing nips though, but would instead start with a project or other contribution