It's odd that you assert this to be "revisionist history" and then go on to make a statement that is itself false.
No other event has shaped Los Angeles like World War II. During the war years Los Angeles experienced a population boom as people moved there to work in defense and aviation. These job opportunities were plentiful in order support the war efforts. The people who came to work in those factories depended on the Red Cars and Yellow Cars as did the factories for getting their worker there. In fact Red Car and Yellow Car ridership peaked during the war years. They were most certainly not allowed to go derelict due to lack of maintenance as they were far too important. In fact there was rubber and fuel rationing at that time which only served to make their operations that much more important.
>"The public did not love streetcars for many reasons. The ride was rough, they were boiling in the summer and freezing in the winter. They forced all manner of people into close quarters with one another. Insufficient capacity meant it was not unusual for riders to cling to the sides of cars where that was possible"
There's a lot wrong with this. Southern California has mild winters and cars were also enclosed with windows that could open and close depending on the weather. There's pictures here which clearly document that [1]. Saying that people had to cling to the sides of the cars is also a complete fabrication. There was nothing on the outside of the cars to cling to.
>"When freeways and buses were presented as an alternative the public embraced building new infrastructure over rebuilding the old."
This is also untrue. The bus began competing with the electric trolleys as early as the 1920s.[2]
>"Blaming some corporate bogeyman is always tempting but does not change the facts."
And yet it's well established fact that National City Lines bought up these mass transit assets and were sued by the DoJ on antitrust grounds for conspiring to monopolize urban transit(they had purchased many other cities transit assets as well.) [3][4]. Conspiracy theory notwithstanding, I don't think it's a stretch to say Detroit and other automotive special interests certainly hastened the decline of the electric trolley.
[1] https://libraries.usc.edu/article/red-cars-and-las-transport...
[2] https://metroprimaryresources.info/our-grand-concourse-histo...
[3] https://www.latimes.com/california/story/2021-11-02/explaini...
[4] https://www.latimes.com/local/california/la-me-california-re...