CCTVs in cities are a big political topic. For corridors that people walk through often, this is much more effective for facial recognition and you don't have to power propellers or deal with crashes. The camera will operate for a decade without incident.
For overhead algorithmic surveillance, just use satellite photos. I fully expect that sat swarms in LEO surveillance will become a thing in my lifetime. Sure there are clouds, but the whole thing is imperfect, the goal isn't to track you 100% of the time and they don't need to anyway.
For persistent surveillance, drones are good for what exactly? Periodically peeking in windows? How many windows would a drone need to look in on a patrol? Can you fly them low enough to actually do this? On a regular route at that, my god.
I'm very worried about tracking with facial recognition and systematic location collecting based on cell signals and satellite car tracking. But this article was about a drone catching people smoking weed after a busybody called 911. The tech is a very marginal sideshow in that story.