If I snatch a phone from the table (probably already locked?) or drop it, I will suck up the additional login.

I have long thought about the utility of a little locking-beacon. If phone suddenly gets out of range, should auto lock. If only Bluetooth were not so unreliable.

These are two different things, since I do not want my phone to have no lock screen just because my headphones are sitting near it, but if it is unlocked and suddenly my headphones disappear, that would be a useful precaution, even if it doesn't eliminate the risk on its own.

I remember that I used the last option many years ago, as that was really convenient and worked very well. Basically as long as the phone was in your hand or pocket it kept unlocked, but as soon as you laid it on a table it got locked.

But now that fingerprint unlock is a thing, I don't even mind unlocking my phone as it is one fluid motion and happens unconsciously.

There's a saying that when something becomes mainstream it is no longer considered AI. Fun to see that being reversed.

Good heuristics. Also that must not be a mainly downward rapid movement, which probably only means you just dropped your phone.

I mean, most people dropping their phone will be too glad/devastated that the device did/didn't escape harm to bother being annoyed that they have to unlock the screen again.