The main problem AirTags and any similar trackers in checked bags pose to airlines is it lets passengers know when the airline is lying to them about where the bags are. That is a tremendous danger to airline operators, particularly when the AirTag user goes public with where the bag went. Example: when a bag was tracked to the home of an airline employee and dozens of other "lost" bags were found there as well or, in this case, a subcontractor the airline trusted:
https://www.nbcnews.com/news/united-...saga-rcna64084 for example.