While logical - this actually is not true. Cases in point - New York says 100 ft - no headway speed allowed. Vermont says A person shall not operate any vessel, except a nonmotorized canoe, a nonmotorized rowboat or a police or emergency vessel, within 200 feet of a divers-down flag. I'm sure there are other examples.This is not true. Boats can operate close to flags IF they are at idle (steerage speed).
everyone would benefit from clear and consistent rules here.