In aggregate, people are correct to feel entitled to get around town without going bankrupt trying. Why would that baffle you?
You're not talking about exceptionally bad drivers, you're talking about half of them. That makes a big difference.
People don't need cars. This is a luxury they based their life one. They can adapt the other way too.
Th number matters for whether it's feasible to implement.
In a large sense everyone is a bad driver.
> People don't need cars. This is a luxury they based their life one. They can adapt the other way too.
People are stuck in situations that need cars. Adaptation without external help would take decades. Tens of millions would suffer badly.
With enough change cars could be turned back into a luxury, but right now they aren't a luxury for most people in the US.
They can bike short distances, but longer trips would depend on access to vehicles they don't own, whether transit or other people's cars.
If you give them enough warning they can adapt. But for a change like this the only solution for many people is "don't live there, good luck moving".
Besides cars are more expensive than riding a bike to a place where public transit is available.