Sensors are cheap and have been around for a long time, but I’m going to guess the number one reason is the small part. Fewer cars = less traffic.

I’ve actually watched a city I visit regularly grow over about 20 years and it went from them having zero traffic to Los Angeles style traffic jams. This is despite their best efforts like making extra wide roads, using roundabouts, etc.

Why are you looking at other countries when literally any state would be better than the shithole you’re in? And even there I think you’ll be perfectly fine in major cities.

But you’re welcome to California. Not prefect, but not fucking Texas.