I agree with you, Canon and Nikon seem like the "Costco" brands so maybe while he pointed them out. But Sonys mirrorless are top of the industry. Fujifilm has great cameras. And you cant forget Leica
Fujifilm, Nikon, and Panasonic are using Sony sensors, however.
And, to a lesser extent now that mirrorless cameras are a thing - their unobtrusiveness.
Do you have a source for that? As far as I remember they have been very secretive about their sensor supply chain.