The pro majors consist only 8 to 14 players vs. to today's 128 is a huge difference. Even today's smallest event(atp 250) consists of at least 32 players. I'm curious to know how many countries participated in the pro majors. The pro major event can only be use against Laver's era. B/c the way i see it is...if there's a bigger pool and more matches to play, the greater chance of getting eliminated. When you have 128 players, the best players and the one who brings their A game will march into deeper round. There's no fluke performance that a player can sneak in deep. You either a better player AND can't have a bad week. As appose to 8/14 players, suppose 6 of the players don't showed up or had a bad week, that would makes it easier for Laver. Sure it would.
And while we can't equate the 60s tournaments today's slam event, but on average, the tournament today has much more weight than in the 60s.
Tier1(goat): Federer; Tier 1.5: Laver, Sampras, Nadal, Borg;
Tier 2: Lendl, Connors, Rosewall; Tier 2.5: McEnroe, Agassi