Years ago, folks hacked a Jeep Wrangler remotely, with a WIRED reporter in the car: https://www.wired.com/2015/07/hackers-remotely-kill-jeep-highway/

That freaked the shit out of vehicle manufacturers. It led to encrypted CANBus messages: https://dev.to/living_syn/can-bus-message-security-3h43

In other words, they deliberately learned exactly the wrong thing from that: they could have taken it as a lesson to not have a fucking transceiver in the damn thing so it couldn’t receive remote messages in the first place, but instead they used it as an self-serving excuse to implement anti-consumer and anti-third-party-repair bullshit.