I imagine if you live on an urban street where (say) kids walk to school and there are various selfish drivers who regularly speed, this could be rather useful.
As much as I dislike the survelience aspects, police operated red-light and speed cameras are already a thing. An app isn't going to fix the problem that your police don't care.
What percentage of communities are rich suburbs that have more money and staff than they really have a use for.
And IMO just covering that small % of communities would satisfy 99% of people making these requests.