Switzerland is spending millions revamping its vast network of bunkers

I'm pretty sure my shelter is under the grocery store across the street from me but the annoying thing is that they don't tell you where your shelter is until you need it. The locations are somewhat secret. I know the location of another civil shelter farther away with the entrance under a highway because it has signs saying it's a shelter...

When I lived in Washington DC instead of shelters everyone had an assigned route for escaping the city by car.

We have an interesting app here in Switzerland - AlertSwiss. It uses your location to warn you about local dangers, like toxic air from a building fire, to landslides, to bad water warnings... you can also see all alerts in Switzerland on a map of the country. Currently there are a couple of landslides and some fires.

How was escape by road was supposed to work? Wouldn't everyone be stuck in traffic as the bombs were falling?

Yes. Almost certainly, the result would be gridlock that would appear chaotic if not for how static and unchanging it is.

So maybe the scenario you describe was always the plan.

After all: Publishing a plan that instills a feeling of preparedness is a lot less costly than building a system that actually works.

In case of nuclear attack, hide under your desks.