Bad traffic is just a consequence of how cities are being built. People might point to car-centric designs, lack of quality public transport, and other problems that only look at the transportation PoV, but a “real” solution needs to change the urban layout to favor short trips and reduce distances.
Cities need regulations that encourage higher autonomy of neighborhoods to reduce this over-reliance on transportation - regardless whether it’s public or private. Policies such as drastically reducing parking spot requirements (parking lots that remain mostly empty and make a terrible use of the horizontal space), enforcing sidewalks and encouraging pedestrian-first layouts, and reforming zoning policies that force everything to be far apart by design.
We can’t expect to have a decent amount of traffic in large urban centers if most need to get across the city to get to work, or drive 10 miles for a grocery trip. This American/suburban lifestyle needs a reform.