Easy to say. Now, how do you implement. The decryption key (or a key to decrypt the key) has to be stored somewhere or entered by the user. Also note that encryption is fast on your computer -- thanks to custom support in hardware. The iPhone has similar. Is this the case for the hardware used in a Tesla? Other vehicles? How is key management handled? Key exchanges? Authentication?
In the case at hand, how is encryption supposed to solve the problem? For mobile data the general idea is to encrypt with a key, and then encrypt the key with a secret (say, a password). "Wiping" the device is achieved by erasing the encrypted key -- very fast. This can work (to a point) even if it is not an encrypted key but the encryption key itself.
I'm not suggesting it isn't solvable or that it shouldn't be solved -- but it isn't as easy as saying "just encrypt it."
Tesla need a "reset to factory" option available from the app that would wipe all personal data, well over-write with 0's.
Apple's encryption works because you're forced to have a PIN, fingerprint of Face-ID, hack any of these and your encryption is worthless. So perhaps Tesla can force the PIN and allow 10x entry before wiping personal.
I don't know, I'm not even a novice in this area.
