Heh, you could be right on this one. But on the other hand, if I was the one filming and I knew a person in the frame wanted more privacy if possible I would be glad to omit them or cut them out.
This discussion isn't about what's polite.
It's about what you think ought to be against the law. And being fined or thrown in jail if you break the law.
You can wear a lanyard today!
It seems like you believe that if the government passed a law then it will have meaning in society? It's still as meaningless as if you just wore one today.
What happens then?