> if you go to an alternate route it may also be congested, and it will all have been for nothing

Yeah, I get that there can also be a bit of a sunk cost thing along with regret minimization going on too. I think game theory suggests that you should switch routes the instant you hit significant congestion though, because P(congestion on the current route)=1 as soon as you hit it.

I think many many people would check local radio, not everyone lives on their phone or in a tech bubble.

Many people don't have a way of listening to local radio outside of their car. Loads of people don't even have a way to watch OTA TV.