Maybe there might be a slot car racing forum that might have more on the history of brushed motors, now if you're talking specifically about 540 cans, then this article here would be a good read:
https://tamiyablog.com/2008/01/tamiy...istory-part-1/

Another pretty good read on the largest brushed motor manufacturer in the world:
https://en.wikipedia.org/wiki/Mabuchi_Motor