And replace them with what? Because if you're not in or at least near a city you'll be stranded without a car.
You not only have to change planning, you also need to change all the existing cities to accomodate that planning
What
On the other hand, I, too, want to live in a house with a green space of my own, and would complain loudly if I was forced to change
There are a few exceptions like London (7 million in the 19th century, 9 million now), but most cities are not London.