This is a "perception is reality" issue IMO.
The fact is they aren't any better or worse than your average vehicle. They command high prices because of perceived quality, and the demand that generates. Lots of anecdotal evidence that they are superior, but not a ton of real data. Toyota service departments are never empty, so clearly they're still in there getting work done right?
I get the reverse feedback from damn near every single person I've talked to about my Audi's. Tons of "Oh my god, those are so expensive to maintain". I've owned two of them now with almost 200k miles driven between them. They break half as often and cost twice as much to repair as my GM vehicles. The resale value on a used Audi is abysmal. I paid $42k for a $75k (sticker) vehicle with only 30k miles on it. Toyotas live on the other end of that spectrum. You can get a used Tundra that is several years older, with more miles for the same price as a younger/newer domestic pickup. They enjoy that perceived quality reputation that was well earned back in the '80's-'90's.
Speaking of reputation......I think that holds some STRONG ties into the market capitalization on the fullsize pickup market. People buy as much on perception, tradition, brand loyalty, and image as they do on functionality, performance, and value. Ram has been their a brand for over a decade now, and people (myself included) still call them Dodge. My dad is a Ford guy, always has been, most likely always will be, for no other reason than "that's the way I've always done it". No value proposition in the world is going to get him to switch. Uncle has a whole feelt (12 I think) of Ford F250's for work. He bought a high end Tremor and it had a TON of problems, he's moved to a Silverado now, and after a year agrees that he should have taken a look around sooner.....Point being, Toyota earned a strong reputation back when the domestics were making crap cars. The domestics have really upped their game in the last 20 years, and are struggling to change that poor reputation. Likewise Hyundai and Kia are fighting similar image issues (although making much better progress than the Big 3 IMO).
I've gone back and looked and this is the closest thing I could find to the study I read (that I mentioned in my last post):
For the third year in a row, General Motors made a strong showing in this J.D. Power dependability study.
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