[tsimionescu]

Except that Lufthansa simply replied by citing a ICAO regulation - no more, no less. They have not "banned AirTags", they simply stated an existing regulation that applies to any aircraft.

Whether they actually enforce that regulation in any way remains to be seen, but they couldn't have given any other answer (or else risk being investigated by civil aviation authorities for not properly observing existing flight safety rules).

If you want to convince anyone that they should allow lithium batteries with some particular characteristics to be used in devices that are not turned on, you don't have to convince Lufthansa or any other airline, you have to convince the ICAO and/or national civil aviation bodies, since it's their rule that Lufthansa was citing.