It's all a moving target, I beginning to believe it's more attitude than anything else, this year 1990 or 1985 is the cut off for vintage, next year 1991 or 1986. Classic, well??
Last month a group of us were riding together, a perfectly restored Porsche 914 rolled by, it was so sweet a classic! Yet, in my younger years, 914's were bottom feeders in my eyes, but now thay have become a thing of beauty. Hence the moving target theory.