Maybe that is a red herring and what Ford got from higher wage was workers that cared about the work they did and made sure the quality was good, as the workers would otherwise end up in a lower-paying job.
When you make "revolutions" such as the first good assembly line, workers that care make a big difference. Faults on assemble lines can be much more expensive than high wage.
Paying your own employees enough for them to buy your product is the perpetual motion machine of business models in the sense that it doesn't actually work. You need other sources of revenue to survive.
Cars used to be luxury goods and the idea of common people like factory workers driving cars absolutely blew people's minds, even if they were the best paid factory workers. The majority of Ford's innovation here was in reducing the cost of manufacturing rather than by paying his workers more. Another point is that assembly line work can be alienating, and being able to own the finished product is probably a decent remedy for that type of alienation.
What Ford got from his well paid people is they didn't quit. Even though assembly lines are easy to train, he still was losing a lot of people because working the same station for months is boring, and so he was constantly having to recruit and train people.
Don't let the above take away from the other factors you mention. The total situation is complex.
Maybe that is a red herring and what Ford got from higher wage was workers that cared about the work they did and made sure the quality was good, as the workers would otherwise end up in a lower-paying job.
When you make "revolutions" such as the first good assembly line, workers that care make a big difference. Faults on assemble lines can be much more expensive than high wage.