It really depends on the card. That is why a lot folks follow the ol' adage, buy the card, not the slab. As someone on here already mentioned, there are plenty of cards in old generation holders that if cracked and resubmitted would get the same grade today. This is my 1964 Aaron. Although in an old slab, I am pretty confident it would get a 7 by today's standards. Although tad off center, it's just a sharp sharp card.....then again, you never know with PSA....maybe it would come back minimum size requirements not met
1964 Topps Aaron .jpg
And then you have Exhibits Hafey that probably today would not get the 4.5 because the corners are a tad too on the worn side and the surface has a tad too much snow.
1929-30 Exhibits Chick Hafey.jpg