It's the same persistent fallacy that comes up again, and again, and again, and again on these boards.
People assume that simply because the grand slam holds the most important events in tennis today, therefore the same always held true historically.
To truly comprehend why Laver is regarded as the greatest of all time, one has to understand the intricacies of the game pertaining to his time. One has to appreciate his dominance on the professional tour and the subsequent excellence in the early years of the open era.
The grand slam is not even in the discussion until 1968!
I suppose we have the media to blame for the spread of this misinformation, because this ghastly cliche about Laver's grand slam is used as a replacement for a well-developed and coherent argument. This results in some kid who thinks he's smarter than everyone else, picking up on some smidgeon of a fact and then smugly announcing to everyone that he's got it all figured out.
Well, thanks very much. If certitude is to be as cherished as knowledge then I suppose we may as well just all stop thinking and accept this awful fatality.
Yeah, to understand the "intricacies" of the game at the time involves acknowledging that tennis was a country club sport that is dwarfed by today's superior infrastructure and talent pool. If you put Vince Spadea in Laver's era and gave him a wooden racquet, he'd destroy his competition! I sometimes wonder if you've seen modern professional tennis in person Cyborg.