[dzhiurgis]

They don't block 100% of sounds, far from it. They block rhythmical noises. So if a piece of metal would come off and scrape the road surface - I wouldn't hear it. But police sirens would be audible.

There are luxury cars than come with Bose's ANC built-in. They'd have the same problem if there was one.

Finally, I never use it in a city, just out on a long drives, where road surface is more ruff and listening a podcast via car system is more difficult than useful.