So yes, information about location is being sent to Apple. No, it's not useful for Apple and it is encrypted in a way that Apple can't get it the underlying data.
> Apple returns the encrypted location of the laptop to your iPad, which can use its private key to decrypt it and tell you the laptop's last known location. Meanwhile, Apple has never seen the decrypted location, and since hashing functions are designed to be irreversible, it can't even use the hashed public keys to collect any information about where the device has been.
https://arstechnica.com/information-technology/2019/06/the-c... gets into the crypto side of it.
So yes, information about location is being sent to Apple. No, it's not useful for Apple and it is encrypted in a way that Apple can't get it the underlying data.
> Apple returns the encrypted location of the laptop to your iPad, which can use its private key to decrypt it and tell you the laptop's last known location. Meanwhile, Apple has never seen the decrypted location, and since hashing functions are designed to be irreversible, it can't even use the hashed public keys to collect any information about where the device has been.