Requiring a permit to cross the bridge was bad writing, change my mind.

[Cleretic]

I think it's more likely that they thought about it but the usual excuses for closing a story-progressing bridge don't really work here.

The bridge can't easily be broken because its whole deal is how ancient and sturdy it is. And the other go-to would be turmoil or hostility in the neighbouring country/zone but that doesn't really fit the rest of the story either.

And again, like I said before: there are actual reasons for needing a pass, they're mentioned in a yellow quest. They're extremely mundane reasons, it's literally just 'this is a singular transport route that we need to keep safe and orderly', but they are reasons.

Personally, I love when the in-universe reason for a thing lines up exactly with the most mundane, real-world reason that would happen. Sure, we're in a big fancy fantasy setting where dragons are real and you can believe your god into existence if you try hard enough, but trade routes still exist.