Earlier quoted context omitted.
That concept has already been implemented. Urban planners who practice it call it "new urbanism". It has been a mixed bag, but is better than the "malls-connected-by-highways" approach of many suburban development s.
Too much density decreases the quality of life. Overcrowdedness, very long waiting times at every establishment or government office, increased ease of pickpockets etc. to "disappear into the crowd", higher prices. You already see all this in many existing cities; you want that, but worse? I'll take malls connected by highways over that any day. Malls are nice and cars are a better experience than transit/walking in…
I'm not sure how you came to this conclusion. There are plusses and minuses to both. IMO, the big plus with a car is freedom, but then there are many negatives like parking, traffic, and speed to destination.
If I ever move again, it will be to a location where I do not have to own a car. I hate everything about driving, and realized it's a huge source of general stress for me personally.