I put an AirTag in my bag for my JFK - LHR - BER trip yesterday and it was a lifesaver. Rather than wait for my bag to arrive, I could see on landing that my bag was still in London and go straight to the lost baggage desk. I showed my AirTag tracking to the agent she and gave me a claim form without batting an eye.
It was very nice not to have to wait for my bag and then wait in line to make a claim after the long journey.