I think you mentioned this once upon a time, Will - but true FSD is only possible if every car is using it. It's those pesky, unpredictable humans that caused the issues for FSD, along with lack of communication between vehicles. (I still agree that solely relying on cameras is a fatal flaw as well)
Imagine swarming cars like we do with drones and one can see a way forward for FSD - it just takes one idiot (or driver committed to chaos) and the whole thing falls apart.