So just to be clear, your steering inputs would be sent to the wheels via a reliable and never buggy piece of tesla software. Sounds fun. Does the patent include a trademark for “phantom steering”?
I would think any such system would be in core firmware stored on an EPROM or similar, with at least one redundant backup.
This is how Teslas currently work for core safety systems like blinkers, throttle, headlights, ABS etc.
These are controlled by firmware and are independent of the MCU software. These systems continue to function even if the main computer crashes. Any future fly-by-wire steering actuator would take the same approach. Suspect other manufacturers would take the same path.