This seems similar to how much of SE Asia requires a “click” sound from camera apps, to prevent surreptitious photos, or how some US states require both parties to consent when recording audio of a conversation. There’s plenty of precedent for privacy laws related to public recording, across the world. And they don’t have to be perfect—the goal is to limit access to casual snooping and creepshots, and to ensure that those who habitually violate privacy can be prosecuted if caught.

Just because you’re in public doesn’t mean it’s ok to take secret upskirt photos, film in the gym showers, etc. There actually is a certain level of privacy expected in public.