Noise pollution from cheap construction is one of the top things driving people away from density

There's certain things that are part of planning and societal laws like the absurdly loud sirens, loud tailpipes, and train noises, but the bulk of the issue with noise pollution is the rate at which air passes through walls in American construction. The alternative is to put more air between you and the noise source - sprawl.

This guy does a good job of explaining what the standards for construction are for energy efficiency in Europe vs the US https://youtu.be/KDXjSpoOQmQ?si=EfDeOlluziexY3KZ . Everything for insulation doubles as noise reduction, and the US has shockingly low standards.

One of the things that baffles me about urban planners is that they failed to realize how something as simple as dense environments being noisy as crap with no building codes to mitigate would be why people want to ditch the city and move out.

I moved into one of those brand new 5 over 1s box apartments in Altanta and after that, I swore I'd never live in multi unit living like that again in my life. It was beyond maddening to have noise constantly, from the train, the neighbor downstairs, neighbor upstairs, dog outside... To be frank I turned to edibles to help me fall asleep and that's not healthy. I moved out to a small town rural setting and love it so much more cause I control the noise in my life now (while paying less for a nicer constructed new house). The 'luxury' apartment was frankly built like shit, and 50% of the new construction in the US is exactly those crap 5 over 1s. I had my mind blown when I visited Germany and experienced a house there where it was dead silent despite my brother yelling (to test) in the room next door.