> "instead of applying engine breaking when the driver takes their foot off the pedal, they went to great lengths to _move the break pedal_ in proportion to the amount of engine breaking that is currently being applied as per the VCUs command"
Regenerative braking slows the car more aggressively than an ICE where you take your foot of the gas, so the pedal change isn't putting on the brakes, it's communicating to a driver used to ICE that the car is slowing more than might be expected.There may also be a sports-related reason for people who habitually left-foot brake.
You clearly have never used a car like that. You develop muscle memory for where the pedal is - finding that the pedal is not where it used to be does not inspire much confidence.
Every other manufacturer has managed to control regen breaking via throttle modulation - even ICE hybrid cars have been doing that for ages.
It depends how much you draw from the motor/generator. One can modulate it as they want, whatever can't go into the battery due to chemistry or drive constraints can be disposed of as heat.