I think you can go even further. Public transit is tough to do well in cities that don't have a certain level of density. They're building subways in LA, but the city just isn't designed for it, patterns of movement are too dynamic, and too much of the city is composed of single-family homes so the last-mile problem is huge. It can only ever have a limited impact at an huge cost. They would be much better off with congestion pricing and dedicated bus lanes on the highways and arterial roads, transitioning these to self-driving when it becomes possible.
Three of the best public transit systems in the world are Berlin, Tokyo, and New York, which are both amongst the densest large cities in the world (Berlin is almost exclusively 5 story apartment buildings). The Berlin subway is largely self-supporting without public subsidy, Tokyo's system is composed of two competing but interoperable systems, the larger of which is privately run, and New York's system was privately run until 1940. The lifestyle, weather, and zoning of the cities where it works kickstarted the construction, and there exists enough demand that they would have great public transit systems even without government initiative.
Three of the best public transit systems in the world are Berlin, Tokyo, and New York, which are both amongst the densest large cities in the world (Berlin is almost exclusively 5 story apartment buildings). The Berlin subway is largely self-supporting without public subsidy, Tokyo's system is composed of two competing but interoperable systems, the larger of which is privately run, and New York's system was privately run until 1940. The lifestyle, weather, and zoning of the cities where it works kickstarted the construction, and there exists enough demand that they would have great public transit systems even without government initiative.