[FractalParadigm]

Realistically, it's been possible on and off for quite some time. Chrysler's UConnect system received quite a bit of flak some years back over just how easy it was to take over full control of a vehicle[0]; not just locking/unlocking doors, but full control over the climate system and wipers, all the way up to starting and stopping the engine or changing gear in the transmission.

[0]: https://jalopnik.com/chryslers-uconnect-vulnerable-to-remote...

[rightbyte]

That is why steer by wire steering is terrifying. If your car turn full left due to some hack or bug at some speed trigger you are dead. And the industry push it as cost cutting.