Where do you live?
It's currently 112 F where I am and there isn't a cloud in the sky. Humidity is very low so water isn't absorbing radiation.
Nobody is riding a bicycle or walking long distances six months of the year here, except for the unhoused, and they can only move at night. Cars are mandatory to participate in the economy.
A car with un-tinted windows is impractical for two reasons: solar heat and UV.
The A/C can be running full blast and my legs will still get hot. Normal side window glass doesn't block UV well so I can get a sunburn with my windows closed.
I have to equip my windows with dark tints. It's like a Canadian putting on snow tires except I can't change it out with the seasons.
So my state doesn't have laws against tints because it can't. Ok, so I drive to another state in my car... now I'm breaking the law.
You can say "human beings shouldn't live in such a place" but first, about 114 million Americans live in similar conditions, and second, these conditions are moving north.
Protecting the occupants of a car against solar radiation is a reasonable thing to do.