How often should I actually deep-clean a carry gun I shoot weekly?

Separate "clean" from "deep clean." After every range trip, run a bore snake, wipe the slide and rails, and re-lube the contact points — that 10-minute job is what keeps a gun running. A full detail strip isn't needed nearly as often; for a modern striker gun, every few hundred rounds or after it's been rained on is plenty. The carry-specific thing people miss: pocket and holster lint builds up around the striker channel and extractor, so even if you're not shooting it much, pull it out monthly, brush that out, and confirm a light film of oil.