Hmmm...
I've been in a lot of Porsches, BMWs, and Audis that were built in the late 80's and early 90's, and they too were big 'ole POS'.
Comparing your 1989 Rattletrap C4 'Vette against your newer Porsche, Audi or even VW isn't exactly a solid footing for a well grounded comparison. My wife's old 1997 Escort had better build quality than most cars from 1988-89, regardless of the manufacturer.
I hear these sort of comparisons all the time..."Back in 198x, when I had a _____, it was a pile of garbage! Ergo, the 2005 version must also be a pile of ______."
I get to drive late model Porsches, Bentleys, Mercedes, BMWs, Jaguars, and so on all the time...it's part of my job...and they all have their strong and weak points. I also get to drive a 1989 Porsche 944 Turbo around DC when I'm there on business (company car), and man...it's no picnic...but I certainly wouldn't use that as the basis for my argument that a new whatever is better than any Porsche, simply because I drove a 1989 Porsche around before...
For every great experience you've had with your C4S or your Audi, there are probably a dozen people who've had bad experiences. The internet's full of bulletin boards where people are complaining about problems with their cars.
While at the GM launch for the C6 'Vette, they quoted some performance figures that indicate the new, base-level C6 is FASTER than the '03 Z06, which was FASTER than the Porsche 911 around a few race tracks.... Quality issues, well...Mercedes ranked near the bottom in a recent ownership survey, and Porsche finished about mid-pack (as reported by Automotive News).
Don't get me wrong - I'm not an American car fanatic either, but I think some of your comments might be a little off-base.