There can be roughly two types of closures on roads. One is that the road is completely closed and driving is absolutely not possible. That's what we have now. Second possible situation is "soft closure", where although the road is publicly closed, some vehicles could still pass because the road itself is drivable.

"Soft closure" can be an event closure like a festival or VIP visit or something else similar, where an emergency vehicle could drive through in case of an emergency. Such soft closures should not close the road completely, but add a small penalty instead, because you can't just drive through a fair with full speed. Of course there must be some mechanism in client (special vehicle type or some option in settings) or partner feed to actually make this data practically usable.