For one, which large cities in NA have any of that? They've got buildings that are not new all over.
Also, what is "new"? I've lived in buildings built in the last 10-15 years that were definitely still paper thin.
Heck we have several tens of meters between us and the neighbors house and we can hear them sometimes.
The other thing is for example balconies. There's not a thermal or insulated wall new building thing in the world that is gonna save you from your downstairs neighbor chain smoking on the balcony all hours of the day. You can't sit outside in the afternoon or on the weekend enjoying life. You can't sleep with the window open (fresh cool air required for proper sleep).
At least because you live in a city without cars you can have the window open during the night without noise pollution, right? We'll sorta because the neighborhood youth is out three stories below, gathering and having "fun" while you are trying to get the baby go to sleep before you yourself pass out from exhaustion. All the while annoying the elderly couple three balconies over with baby cries yourself.
Look I don't mind if you want to live with those things. No issues at all. If you love it, go for it.
Just don't make me do it.
And yes I've lived in properly built concrete apartments where I did not hear my neighbors at all and I had no balcony and I was able to open my windows without issue. Not in NA and I had one of the very luckily located apartments out of like 100 in that building.
I've also lived in concrete apartments with a balcony and all the problems I described earlier. Never again as long as I can help it.
As for putting dwelling further apart, that's why we have the suburbs.
When Boeing or Airbus announce a new airplane, they come up with all sorts of luxurious concepts that would make air travel less miserable if not enjoyable. We all know damn well that the airlines aren't going to do any of that except maybe for first class. Housing is the same. Cheap out on everything, pack 'em in, profit. Then when there's a big fire or it all falls down, close up and start again under a different name.