I agree that blocking human sounds would be the best thing ever, but noise cancellation is still good for allowing you to keep audio turned down lower. When com

I agree that blocking human sounds would be the best thing ever, but noise cancellation is still good for allowing you to keep audio turned down lower. When competing with other background noise it's very easy to push the volume higher than is good for your ears. Also, if by hearing the oncoming traffic you mean that you've tried ANC headphones while driving: please don't wear any sort of headphones when operating a vehicle. Music is already distracting, cutting off the world on top of that is even worse. And also likely to be illegal. Even if not specifically called out in law, there's a good chance it will be considered distracted driving.