GP is making the assertion that Airtags are cargo tracking devices powered by a button cell, which this document issued in 2021 (note the document referenced in that thread is from 2017) appears to exempt from those requirements (both from a battery point of view, and from the wireless signal one). IMO it's hard to argue that they're not, but then the question in my mind becomes "is checked baggage cargo?" for the purpose of these rules. No idea.