The air pollution problem that commuting causes may be negated in the future with increases of working from home. I don't see how energy is significantly cheaper in the city vs. in suburbs or rural areas, aside from transmission costs. To which economies of scale do you refer, and how would cities become more comfortable? I assume maybe you mean cheaper? Housing costs, for instance, aren't actually lower, people just live in disgustingly small spaces.

I think you're mistaken about the inclinations of the average person. People like having a decent amount of living space. I don't think most would want to give up a back yard.

How about people who don't want to live in a dense urban environment, no matter much an economist tells them that the "economies of scale" of a city are more favourable for the statistical model they happen to believe in the most?

Current access to cheap everything! As a whole, the suburban lifestyle has a greater reliance on the fruits of globalization.

I don't think we're guaranteed a future where we can rely on globally sourced cheap products materials and labor.

Not making any predictions about that, though. Just saying that if globalization wasn't a thing, cities would be more important.

Why should cities become more comfortable ? Just make up policies that forces/incentivizes people to move to the city and voilà.