They really should have just marketed the software "as-is" to whatever extent that is allowed by law. I guess they didn't because deployed automobile software is probably not allowed to be considered experimental.
Still, comms that framed it like: "This software purchase upgrades your car with state-of-the-art autonomy capabilities from our AI team, as we approach full self-driving" would have been more honest, still exciting to consumers, and avoided over-promising.