Wild. My experience has been if you live in the city long enough you don't even notice the noise. I've lived downtown for 10+ years in different major cities. There's a building being built directly behind me right now and I hear them all day long and it doesn't even phase me anymore. I'm also on a major drag where people drink all week long and walk around shouting at each other.
I kind of like it over the creepiness of being in a quiet empty house with nobody nearby..
I notice gunshots for sure but haven't heard many (any?) of those in Denver vs Dallas.
I've been living in a big European city for more than ten years now. I can kinda forget about the noises surrounding me, but I always tend to feel less tense when I leave for the countryside. And when I get back, sure enough, I hear all the random noises again. Upstairs neighbor dragging a chair when sitting at the table. Other neighbor taking a piss. Neighbor from across, blasting his TV or his kid crying for whatever reason.
There is never a moment of respite in the city. You wake up, you got your neighbors doign their thing. On your way to the office / park / groceries, you got the traffic noise. At the office: the AC hum and useless office chat. On the way home, traffic again. Back home? Neighbors are back, too.
It's quite possible that we're in a vicious cycle where low contentiousness causes people to be more isolated and more cynical and that in turn may cause some people to be less considerate of others, but if that's true it's still a systemic problem and at an individual level looking for more isolation is the only reasonable solution.