I think the primary problem here is the rural-urban migration; people the world over are moving from villages and small towns to large cities for work and other opportunities. This is a truly global phenomenon with the share of people living in cities rising from 55% in 2018 to a projected 68% in 2050. [0]

Housing and transportation policies are secondary in that they have failed to adequately address this first problem.

The solution is entirely new cities built to meet the demands of the twenty-first century.

[0] https://population.un.org/wup/Publications/Files/WUP2018-Key...