However bad you think it is it's safe to assume it's way worse. Radar (not visible light) algorithms that I wasn't privy to the details of could track hundreds of vehicles and dismounts circa 2010. Our "test data" was a recording taken over a Washington DC suburb (so not downtown Manhattan, but still thousands of cars, hundreds upon hundreds of pedestrians joggers, cyclists, etc.) This was done with a single bajillion dollar military radar. This was a production system and not even the latest and greatest at the time. Imagine what far more far cheaper, albeit with worse receiver hardware drones can do in the visible spectrum.
However bad you think it is it's safe to assume it's way worse. Radar (not visible light) algorithms that I wasn't privy to the details of could track hundreds of vehicles and dismounts circa 2010. Our "test data" was a recording taken over a Washington DC suburb (so not downtown Manhattan, but still thousands of cars, hundreds upon hundreds of pedestrians joggers, cyclists, etc.) This was done with a single bajillion dollar military radar. This was a production system and not even the latest and greatest at the time. Imagine what far more far cheaper, albeit with worse receiver hardware drones can do in the visible spectrum.