The reason why I am opposed to such laws, as a cyclist, is the intent is to harass cyclists. My area has a law that forbids vehicles from passing within one meter of cyclists. The police won't do anything if a motorist actually strikes a cyclist unless there is injury. Yet motorists want the same standard actually applied to cyclist. Notice the asymmetry?
(Incidentally, I do ensure there is clearance when I pass and I avoid passing on the right. But that has more to do with being predictable and valuing my life than the law.)
Where I'm at, cars are only allowed to pass a bike if they can leave 1,5m of clearance. There is no minimum for the reverse situation
Of course, even the police gets angry at the cyclists for not getting out of the way instead
Enforcing such a law would remove the vast majority of dangerous interactions between cars and bikes.