You can't fix traffic. Its impossible.

There is a concept called induced demand, we have known about it for decades. There are basically two concepts behind it. Basically, it breaks down to time.

No matter how much you improve traffic, it will never change. Even if you add lightrails,trollies, etc. You will never alleviate traffic. People will decide to drive to work on the pure principal of how long it takes them to get to work. The more you reduce traffic, the more people will just replace those who are no longer driving.

I can't remember the exact time, but something like, the magic time people are willing to commute is 45 minute. So if you add a ton of transit and 50% people more take transit, those 50% people get replaced with drivers who are now thinking "Oh man, driving is so much better now!" and things rapidly climb back up to where they were.

So the trick is to stop investing into supporting more cars, that traffic will never die down, but you can force more and more people to take transit options and increase the rate of improvement on that.