Just how California had laws that effectively forced automakers to make nationwide changes, Europe can still mandate this and it may end up here regardless.
I don’t think it will have as much of an effect on the auto industry I’m afraid, the auto industry is already well used to having multiple regional models to comply with weird country quirks of their own vehicle safety boards.
Any EU mandate will just get through onto the already existing model destined for EU countries. Unless the EU writes it in such a way to force companies to abide by it in all countries even non-EU, but that would be a legal gray area for sure.
It works for Cali because no company is going to have multiple regional region cars (i.e. states), that would be a step to far for them lol