There are cheap trackers from aliexpress that can be used in place of airtags. Most include GPS and use mobile internet for sending location updates. May be the airtags made tech based stalking more popular but will it reverse just because Apple takes it back. Also its not like finding where someone lives is a particularly difficult task given the ridiculous amount of information there is online. And as for the public transit example, may be all they have to do is wait till the victim gets down the from the bus to find out where they live ? (I mean it is public transit after all).