Changing the results just when you are going to action on them is a fundamental UX sin.

Yes. "UI Speed" should be a configurable thing, so that if the UI changes as you're choosing an item, it acts instead on _what was there_ at a brief moment in the past, e.g. 20-50ms ago.

I'm hit by this problem often. I wonder why UI updates which could well be incremental instead just replace the whole results from under your fingers!

Don't worry, airdrop does it too! I've accidentally sent airdrop requests to strangers from their profile picture moving under my finger as I'm approaching to touch someone else's. The single most idiotic design I've ever seen in UI. I don't use airdrop for anything sensitive anymore, obviously.