>Part of the reason modern lots are so big and why parking covers so much area is simply because cars are too big!
Spaces are typically 9' apart. I've seen some new ones that have moved to 10'. But part of the reason for "large parking lots" is the building code requires a minimum number of spaces for a building of a certain occupancy.
>There is zero reason a person needs to own a 7 seat SUV to transport 3 people or five 2x4s twice a year.
While I agree, people do this because everybody else does it. If you're in a Mini, surrounded by Escalades, the Escalade starts to look a lot more attractive.
We went through all this in the 90s. The SUV explosion was because women like it. They like feeling safe; they like being up high; the car companies discovered this, and made the SUV a really comfy place.
There is no regulation that will fix this. You want to fix it? Make cities and public transportation livable again. It's really not that difficult. A safe, affordable, well-managed city with good schools would be attractive. The problem is achieving this will make certain people unhappy. Pick which one you want more.