Believe it or not, the used car market changed drastically. I regularly shop around for cheap beater cars to fix up. Before the program, there was never a problem finding a running car for $500. It was also easier to find used parts, as cars would go through a part out process before recycling. The program required the cars to be crushed with no hope of salvaging good parts from them.

~700,000 cars were crushed.

~170,000,000 new cars have been sold in the meantime (so assume tens of millions of used car transactions related to that).

It was a blip. It's more likely that other factors are driving the change in the market.