People walk out of their flat, take the lift to the garage (avoiding eye contact), sit alone in their car, spend 30 minutes grumbling at the traffic and other drivers' behaviour, park on the company lot, walk out of the office 10 hours later, sit alone in their car, spend 40 minutes (dammit!) bitching about the traffic and other drivers' behaviour, stop at the supermarket, say hello-thanks-goodbye to the cashier, spend 10 minutes in their car, park into their garage, take the lift to their flat (avoiding eye contact), open and lock the door. Repeat on the next day.

You can replace the garage and the car by the fastest possible walk to the underground station, grumbling at slower people, and 30 minutes in the tube, avoiding any eye contact by looking at their smartphone/newspaper/book and avoiding any other interaction with headphone.

And on Friday afternoon or evening, they get out of the city as fast as possible, until Sunday evening.

That's "social beings enjoying spending time with other humans in cities". You don't even know 2 people in your own building, when you live in a city. You can lay on the side-walk having a cardiac arrest and people will walk by you, if not over you.

People want to live in dense regions because they want to have good restaurants and good public services and things to do on the weekend outside of their homes, other than hunting and fishing.

So this:

> And on Friday afternoon or evening, they get out of the city as fast as possible, until Sunday evening.

This isn't universal. Not even close.

Plus, you can't ignore the political aspect: Someone with progressive politics will be happier in a city than the country, at least in America, and that's been true a very long time.