And they are compensating not hearing with extra checking a blind spot, being hyper aware of their surroundings.

But the average driving idiot with noise cancelling headphones isn’t likely to be more aware of their surroundings. It’s actually been suggested and I think even taught in driving classes that you shouldn’t drive with headphones on. I’m not just pulling it out of nowhere.
https://www.drivingtests.co.nz/resources/are-you-allowed-to-wear-headphones-while-you-drive-a-car-or-ride-a-motorbike/
Just one example but most links are saying not a good idea.

Not only because you might not hear a honk. Also when you have all sounds shut out but your music, you can be less aware of your surroundings in general, or less aware of the speed you’re going. For example once driving to Vegas I got a speeding ticket because I was going way faster than I thought since I was distracted by a YouTube video I was listening to.

The main point is, it can be unsafe for more reasons than just not hearing a horn.