You didn’t mention smart traffic signals. Essentially streets are an X-Y grid with intersection points controlled by switches. The math to optimize flow through that grid based on dynamic load balancing must have been done years ago.
If the red/green light duration is variable between 10 seconds and 60 seconds (or full on/off when there is no cross traffic) you should be able to increase throughput by at least 25%.
Why aren’t traffic signal/cameras already tied into city-wide or, better, county-wide dynamic management systems? — David Grace