The airpod could send the phone a public key + apple's signature for that key, then the phone could do challenge-response against that key. That would mean the

The airpod could send the phone a public key + apple's signature for that key, then the phone could do challenge-response against that key. That would mean the scammers would have to exfiltrate the private key from a legit pair of airpods, which would hopefully be much more expensive