It's not all historical accident. The US also bought into a vision of an auto-centric future that featured multi-lane highways right through downtown neighborhoods. This vision was pushed by specific people, notably Robert Moses[1], who advocated strongly for highway systems over public transport, and who succeeded in having a number of dense urban neighborhoods demolished to make way for highways.

There was also the General Motors street car conspiracy[2], which saw car companies buy up privatized public transit only to run it into the ground.

The fight against this future being imposed is also fascinating reading, particularly the work of Jane Jacobs[3]. She correctly saw past the hyperbole to the unfortunate consequences, fought against the vision but lost.

The reason not much infrastructure is being built these days is simply that cities are running out of money and credit. Every road built comes with a price tag for building it, and an ongoing price tag for maintaining it. The building price was so often done on credit (bonds), but the maintenance price is usually not considered. Given that roads bring in basically zero income for a city, every road built comes with an obligation for the city but no way to pay for it. In the past credit was issued on the assumption that future growth would somehow provide some payback, but after 50 years cities have hit the growth limits and still not seen any payback. Strong Towns[4] is an excellent book on the subject.

[1] https://en.wikipedia.org/wiki/Robert_Moses [2] https://en.wikipedia.org/wiki/General_Motors_streetcar_consp... [3] https://shelterforce.org/2016/05/10/jane-jacobs-defender-of-... [4] https://www.strongtowns.org/book