You would need to have lived in the era to understand fully.
In 1972, you had this.
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and this
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in 1973 you had this. Notice the bumper?
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1973, and the 70s, and some of the 80s were bad years for cars.
In 1972, you could buy a monster Corvette with a 454 engine and gobs of horspower. In 1973, the Vette you could buy was a watered down version of its old self. The 427's and 454's were gone.
1st up: The insurance companies were leaning hard on the car makers to make cars that could withstand minor bumps with out costing fortunes to repair. So, to answer the insurance companies monetary and political pull, the car makers installed larger bumpers that "stuck out like a sore thumb". The red Mustang and gold Chevelle had bumpers that weren't cutting it and the huge bumper on the black Chevelle was Detroit's answer to satisfy the insurance companies . The bumper on the black car looks quite normal now, but at the time we thought they were ugly. They took a little bit to get used to.
2nd up: We went thru a gasoline crisis with shortages, gas lines, and increased gas prices. And the car makers were dealing with how to control automobile emissions.
What worked in 1972 did not work in 1973. The cars made were uglier, some were made smaller, and they were all underpowered. Plus President Nixon, in an effort to maintain some kind of control of energy usage cut the speed limits, nationwide, on all highways, to 55 mph.
The cute little Mustang II was introduced in 1973. It was underpowered and loaded up with pollution control crap ( witness, I am not anti-pollution control, but it took the car makers a few years to start making good pollution control equipment for cars). And it had those huge bumpers.
Add in that with the increase in gas prices, people started buying the Toyotas and Datsuns and were finding out they were reliable, cheap driving cars and the little Mustang II did not have much of a chance.
Basically, the 70s and the early part 80s sort of sucked for car selection.
Cadillac entered the small car, economy car market with this beauty:
The Cimmeron. Which was just a Chevy larded up with all of toys a Cadillac was expected to have, and with a Cadillac badge slapped on. And a Cadillac price.
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All of the US cars were junk back then. There was the Chevy Vega, which if you left the east coast with a new car you arrived on the west coast in a bucket of rust.
There was even a 60 Minutes interview with Henry Ford II saying, " We build lots of lousy cars."
The mustang II was just not born at a good time.
Eventually, Detroit got its act together but there was a big change that allowed that to happen.
In 1983 or 1984 you could walk into a dealership and buy a new car for $3995.00. In 1984 or 1985, the same car would cost you $14,999.00. It was called "sticker shock". Overnight, from one year model to the following year model, Detroit jacked it prices. OMG, $15,000.00 for a car? 4 years earlier I paid "only" $33K for my house---which I could have bought for $15K four years earlier. $15K for an average Joe Suburb kind of car? GTF outta here !
The cars are better now. Yep. They don't make them like they used to. Used to be if got 50,000 miles out of your car you were doing real good. Many were in the salvage yards at 50K miles. Nowadays, 250,000 miles and more is the norm.
But I digress 
The little Mustang II was born at a bad time. And the blue and white Cobra paint job was about all you got; A ho-hummer with a super paint job price. I suppose the other book end would be the under-powered, overheating Pontiac Fiero 
High priced gas. 55 mph speed limits---and CB radios (Radio Shack loved 55 mph. You have not lived if you never walked into a Radio Shack and saw three walls in the store covered up with CB radios in all brands and styles).
You can talk about the Magical 70s, but in the automotive world there were some dark days ahead.
Wichita, KS
