Well... It looks like the Bloomington Gold Corvette guys invented the term and they are saying that 80% for "gold" status in all four sections. Interior, exterior, engine compartment, chassis. 66% for "Silver" and 50% for "Bronze".
So... There's the standard... Is that air cleaner etc. 50% of the engine compartment? I think it's less than the 20% of what's there... But even at 50%, in that definition, it's a survivor.
You know... I said I've seen this car personally and it is really nice. I also know Ralph well enough to say that he is not going to intentionally misrepresent what this car is or isn't.
If you don't like the car, don't buy it. If you want to rip on the description, I guess you can, but I don't get the reasoning behind it. It's a nice car and IMHO, it's priced fairly.