Some freeways, especially near more affluent communities, do have sound padding walls to help mitigate sound. Presumably a regulatory body would be advocating

Some freeways, especially near more affluent communities, do have sound padding walls to help mitigate sound. Presumably a regulatory body would be advocating for making those part of the code, alongside helping developing new technology. There was a good 99% Invisible recently on those headlight reflectors embedded in the asphalt, that’s a good example of where constraints (No lights during WW2 for fear of bombing) created the atmosphere for innovation. Regulations can artificially create those constraints as well.