Negatives acknowledged, there are huge efficiency upsides to dense human living. Everything becomes smoother, faster, less wasteful. You get a society that leverages economies of scale for everything.
This is also why communist countries had stuff like dense housing in deeply rural areas, and why most people were shuffled into cities. Big houses and properties do nothing for the state and just encumber society. Way easier if everyone just lives in their tightly packed central shoe box.
Anyway if you densify cities you can slow down the sprawl and maybe keep suburbs actually smaller? a few more ten story apartment blocks downtown might house the people who have to live in your area and commute.
Yes, this is the crux. Loud, smelly, concrete cities suck. And you’re right that density alone would lead to this.
What we’d ideally want is cities that can be dense without being loud, smelly, and dangerous. These cities exist: Amsterdam, Copenhagen, Zurich, Utrecht, Freiburg, etc.
We can’t do this in the US because we can’t remove the source of the noise/danger/stink/concrete problem: cars.
And that’s the catch 22: In the US everyone gets around by car, so density becomes undesirable. We can’t densify because density + cars is bad, and we can’t reduce cars because it’s not dense enough for public transit to get better.
Individuals get stuck in a prisoner’s dilemma where driving is safer, more comfortable, and faster than transit. So every individual with the means to drive chooses to drive. Public transit becomes branded as something for poor people. The concrete honeycomb fills up. The downtown becomes a noisy disaster. People can no longer imagine that good cities are possible.
Vegans gave us the Impossible Burger, which I'll eat instead of regular burgers when available. What might anti-car people trigger as a positive?
1) sometimes it is noisy at night, usually because of people in cars, but sometimes because of people not in cars;
2) sometimes it takes longer than needed to walk somewhere, due to intersections
3) my house is not as big as I would like. (I think this applies to many people regardless of how big their house is.)
4) the busses are always late in winter
Indeed, the way we have effectively banned density everywhere is wildly inappropriate. Cities should allow dense development. That is, after all, the whole idea of cities: attain the benefits of agglomeration. Cities rejecting anything other than detached single family houses in most of their footprints is contradictory to their purpose.