Sorry, but this is bullshit pedaled by people who've never given an ounce of thought to the economics of car buying.
C4C effected 700k cars from the 90s, all of which were worth less than $3,000. There were, at the time, roughly 250 million registered vehicles on the road. There's absolutely no chance that this had any effect what-so-ever on the market for used cars. 700k is literally a rounding error when compared to 250 million.
What hurt the used car market was the fact that new car sales fell from roughly 15 million a year in 2008, to 9 million a year a year in 2009. It took until 2015 before cars sales reached that of 2008.
All told 40 million fewer cars were produced between 2009 and 2015 compared with how many would have been produced if not for the GFC.
Those 40 million cars that were never produced are what caused used car prices to spike. Not the 700k Ford Windstars and Explorers lost to C4C. Anyone who tells you different is a fool.