I think you’re referring to something I’ve said on occasion before but that is actually not what I said.
The supply of raw cards was on average more mint in the past. That’s a mathematical fact. The average WOTC card submitted to PSA was more mint in the past. That’s because the lower grade market has developed.
If you limit the analysis range to only looking at PSA 10s, and specifically the best examples of PSA 10s (not ones we would probably all agree should be PSA 9) no there’s no reason to think that old PSA 10s are more mint than new ones, or vice versa. Because the best copies pulled from packs are going to look the same whether the year is 2014 or 2024
That’s what I’ve said. If we’re talking about the average PSA 10 in the wild, the story is different. Overgraded copies don’t get regraded. Undergraded copies are cracked and resubmitted/cross graded. Stonger copies are kept in collections, weaker copies are more likely to be resold. PSA being more particular about expensive cards is also a factor.
But yes, I agree that this thread should not be about old vs new cert. If you want to continue this discussion just ask and I’ll break it off into it’s own thread.