One foot EV driving does turn on the brake lights when it exceeds a certain deceleration amount.
But most EVs default to slowly charging the car and slowing it in a similar way to ICE compression braking (which uses 0 fuel in fuel injected cars BTW).
Anyway regardless of how the vehicle is slowing down, the NHTSA allows for the brake lights to be activated by other devices that slow the car (not just the pedal), and the UN requires brake lights be applied if the vehicle deceleration exceeds
That is not the case in the US or in the EU. Things like GM and Hyundai won't even show the brakes with the foot completely off on full regen. You will specifically say you cannot do have a secondary braking systems as well which is where I think the issue comes in. BMW and Mercedes both only show brake lights when you fully remove your foot from the accelerator with regen turned on