More money flows atop highway and road infrastructure than on biking, rail, and scooter infrastructure. By orders of magnitude.
Commuter rail has 1/200th the economic impact of interstate highways.
Biking infrastructure is actually deleterious as it doesn't serve the pregnant, elderly, sick, frail, doesn't work well for rain/snow/high heat/weather, doesn't transport high volumes of goods, etc. etc.
Lots of cities are tearing up road infra to cater to this, and in doing so, they're reducing the economic corridor capacity and throughput of roads. Roads are simply much more valuable and flexible for logistics, people, and business.
The value of roads is going to become even more apparent when we have widespread autonomous vehicles.
Bikes are popular for 20-40-something men, mostly yuppie, mostly upper middle class. But they're not doing the economic heavy lifting.