People can get as upset as they wish. The economy of volume is a factor in favor of vintage. Advances in design and manufacturing techniques favor modern models. My experience is that at the $300 price point you cite, the vintage models absolutely spank their modern rivals. But there are lots of price points and the best of the best being made now is probably the best there has ever been.
You also have to recognize that inflation over the decades makes the comparison invalid. For example, my JVC QL-A7 sold for $350 in 1978. It will destroy any $350 table made today, but it isn't a fair fight. To get a fair fight you have to adjust for real dollars, so my JVC is actually a $1450 table today. At that price, it can run right with the pack of modern tables. Not really better or worse, just on par. However, since I bought it a decade ago for $125, I know I got amazing value and that's all I'm really concerned with.