Rail can't take you to suburbs is basically the main reason this happened.

The suburb was invented by/for the train. We called the first ones "street car suburbs" for good reason - the rail was why they were even possible in the first place. Cars work better than rails in suburbs (no congestion) and so rails have mostly disappeared, but rails absolutely could work in suburbs again if we invested in making them fast and frequent (which is expensive so we won't)

Look at South London - train to suburbs is normal

Ever heard of trams and busses?