"These industries collaborated in disassembling what was, in retrospect, a wisely-conceived urban public transit infrastructure."
That myth was discredited long ago.
The trains and trolleys "back then" were the only alternative to riding a horse. People would walk blocks to reach the tracks because they had no other choice. Then along came the automobile, and as prices dropped people bought them because cars gave them freedom, gave them options. Their lives weren't restricted by train timetables.
As more automobiles were sold, ridership on trolleys greatly decreased. What was once a profitable venture now became a financial loss, and the private companies who ran much of the public transportation sold their infrastructure at a great loss to whomever would buy them. Many simply went out of business.
Did Ford and Shell Oil collude to destroy public transportation? No, because it was already destroying itself. That's the way our world evolved.