PR events sit completely parallel with patches. I considered whether grasp servers should accept patch git data as refs/nostr/ or even generate the ref when patch events are received.
For:
1. clients that choose just to implement only PRs could easily extend to add basic support for patches by treating them as PRs (root patch map to the PR event and additional patches map to PR updates but follow nip10 rather than nip22).
Against:
1. it encourages clients not to implement applying patches
2. patches not sent to a grasp server wouldn't show up in these clients. Showing some but not all is bad UX.
3. patches not accepted by the repository grasp servers wouldn't show up (there are no grasp server hints like in PR events).
4. its another thing for grasp servers to implement