You're assuming that a z32 is the only option for a potential buyer, but the opportunity costs of a newer vehicle make the z32 a tough choice for many. There's a reason why many of us are engineers and techie people; we're willing to deal with the headaches because they offer a real challenge and a greater payoff. When choosing a vehicle, "challenging and pricey to maintain" don't appear very appealing to many; we've lost the market we used to have and thus the value is lowered to the level the economy will tolerate.
Economics make your arguments invalid.
Cheers, JBrobst
"A life spent making mistakes is not only more honorable, but more useful than a life spent doing nothing." George Bernard Shaw