Yeah, it's expanding a rabbit hole they've already opened. Here's the 1969 Topps Nolan Ryan.
1969 Topps - [Base] #533 - Nolan Ryan
Courtesy of COMC.com
It's up to them, just seems bizarre that they're only recognizing the 3 in the same set, when there are 25 or so from just 1973.
Registry guys who want to improve their set ranking could buy them and get them added, then hold the higher positions in the interim while everyone else catches up.