A chat AI trained on nostr notes data
Would open up a whole new world of search queries
Would even enable features like "show related notes" or "show profiles with similar interests", etc
Discussion
I don't think these features require ChatGPT specifically, and I'm not sure ChatGPT could point you to specific notes - it could probably summarize stuff or answer questions. But I've never used it, so it's just a speculation.
Besides, people are quite hostile to algorithms here, and ChatGPT-based algo should totally freak everyone out :)