My daily is an s550, that I bought with 3k miles for 33% off MSRPIf the 2024 Mustang had the same performance, technology, safety, fit/finish, etc as a 1964...it'd be cheaper. Your examples are comparing apples to oranges because so many things have changed over the last 60 years.
It's not worth debating, obviously you disagree and no matter how many facts I can present, you won't change your mind. There's a reason you're driving a 20 year old sportscar.
This is my point though, the mustang was supposed to be affordable, not have all the bells and whistles.
As @DSG2003Mach1 said, the real issue is lack of wage growth, unfortunately the other side of the coin also matters. We will use his example of the camry vs inflation going back to 1990. The camry price actually rose slower than inflation 77% to 124% whereas the best selling ford rose 231% in the same time. Overall msrp vs average living wage is a totally different comparison where all car prices vastly outpaced incomes. Value for the dollar will always be compared as buying power vs quality. So going back yo my original statement we can loosely translate the apples to oranges argument to "is a better suspension, extra airbags and lane assist worth a 2nd car?" Eventually the innovation excludes the price point of the original buyers market.
Again, my comparison was relitive price. The 04 cobra was much more innovative than the 64 secretary's car but held the same salary to cost ratio. There were lightyears more tech from 64 to 04 and four times as long while still hitting the same price point vs 10 years to the 14 gt500 with less of a tech bump and a 25% increase in the ratio.