There could be a DoS attack vector - presumably a BLE-enabled microcontroller could technically emulate an infinite number of AirTags and drain the battery even more if not cause more serious problems. I wonder how quickly this would be fixed if someone were to sprinkle a few such microcontrollers around Apple Stores or offices.
Someone already reversed the exact protocol and proof of concepted a arduino (or pi?) device that could happily use the network and would roll the keys regardless of whether it was in the owners vicinity, defeating the anti-tracking stuff.
Of course at that point you’ve probably spent more than regular gps stalkerware
You are possibly at risk of Apple detecting this and locking your account. But at some point, if the attacker is determined enough to build custom hardware like this, there is not a lot you can do. None of the competitors managed any better or even got close to the protections Apple provided.
At some point we need to put the burden on law enforcement. It's impossible to make abuse of technology impossible but we can criminalize misuse.
However, do most wireless protocols cause listening devices to start using significantly more CPU and thus battery power? I'd expect DoS in most authenticated protocols to be impossible and essentially rejected at the hardware level (just like interference would be) with very minimal power impact.
