(I know I'm two months late)

To back up what you're saying, I work with ML, and the guy next to me does ML for traffic signal controllers. He basically established the benchmark for traffic signal simulators for reinforcement learning.

Nothing works. All of the cutting edge reinforment algorithms, all the existing publications, some of which train for months, all perform worse than "fixed policy" controllers. The issue isn't the brains of the system, its the fact that stoplights are fricken blind to what is happing.