I would put like four figures into a kickstarter if somebody would make some kind of solar-panel+webcam+18650+microphones+arduino kit that can be strapped to every telephone pole and traffic light that just feeds back data on what license plates honk when and where to a public dataset.
Welcome to Shanghai, we have it, provided by the government. 5 years ago it was such a cacophony, then they passed the law forbidding honking, and now cars just flash their lights like crazy. Scooters still honk though, but since they're all EV and otherwise pretty quiet, it's a reasonable enough tradeoff.
Russia also has regulations forbidding the honking within cities except for signaling immediate danger, and it seems to work well, somebody would honk for no good reason sometimes, but the fellow drivers wouldn't approve of it. The lack of automatic enforcement allows to use it sparingly to e.g. wake up somebody at the traffic light and not worry about protesting the fines.
