Right - unless you’re getting a custom home, builders do jack shit about noise control - at best, you’ll have some fiberglass batting inside an interior wall, but even that is usually not done. Take the same kind of standard cost-cutting and apply it to an apartment complex, and congratulations, you just created the projects. My point being is that if residential density is a desired social policy, then there need to be standards put in place that focus on quality of life, not just safety/environmental standards. But builders and developers have regulatory capture (in the US), and things like “quality of life” are marketing premiums rather than something everyone should enjoy.