Yup, and conversely, a transmission overhaul by a professional shop back then was $250.00. So, while your perspective is right-on, it DOES have 2 sides! Today, transmission overhauls can and do approach 9 grand on the more complex units. Mere 4 and 5 speed units are dwelling in the $3500 to $5000 range. 250 dollars in 1970 isn't even close to those figures, figuring inflation.
My parents' mortgage was a whopping $78.00 per month on a 30 year, 4% mortgage. It ran from April, 1956 thru 1984. They paid it off a couple of years early.
THAT very house was egregiously damaged in the 2021 Texas freeze. Inasmuch as Dad had passed on in 2015, and Mom was 87 at that time, she let the insurance company gut the house, and basically made the whole thing new inside, including ALL plumbing and electrical wiring replaced, to bring it up to code. (The electrical outlets never had ground prongs, for instance, and well, nearly 70 year old plumbing is what failed in the first place.
The prices of homes skyrocketed during that time, so she sold it and is, at 91, living the life in assisted living. She still has her car and drives.
Lastly, the average cost of a CAR today is 49 grand, last I read. So, the cost of cars has outstripped inflation, AND they are STILL a net-zero financial liability.... NOT an asset, like the fibbers of the financial world like to make unwitting consumers believe.
The Ivory tower bean counters knew and still know these dynamics. They are also keenly aware that most people are myopic when someone says "It is only $600.00 a month". I wonder just how many folks read the truth-in-lending disclosure on their contract and see how boffed they really are.
That is one thing that EVERY financial guru from Jonathon Pond to Dave Ramsey got dead right.