Many city planners believe that stopping traffic frequently makes the city safer. This isn't true, of course. But, it seems true and it's easy to believe. If a city timed major traffic ways properly, it's been shown that accidents are reduced. But, facts are so inconvenient. Rather, lights are timed poorly which causes greater pollution and tension. The drivers, seeking a more optimal path, start taking side roads and neighbors complain. So, the city, rather than improving the efficiency of their roads, make the neighborhood streets less attractive by adding stop signs and speed bumps.
The other factor is the profit motive. Frustrated drivers who have limited options for side streets become increasingly likely to slip through changing lights or speed between signals. The result is, of course, greater revenue for the city. You'll note, this is also a completely unsafe situation. Ideally, our municipalities are there to make things better, easier, safer. Here, they're not -- yet, no one seems to complain.
What you can do, rather than introducing yet another optimization agent (humans do this pretty well), is organize a social movement to make your streets safer through applying demonstratively better solutions with existing technology. For instance, why do demand lights initiate an immediate change rather than simply queuing the change durning the next light cycle? Negligence and miserliness.