It is, but it's also that the other 3 majors (as well as the YEC) are far more correlative to each other.
Remember that pre-88 both AO and W were on grass and USO was on fast HC. In fact, if you look at the list of players who have won both W and USO, you will see they are fairly well correlated.
So you can say that ATGs were cursed at RG but you can also say that ATGs were helped by having more of the big tournaments on fast surfaces. Even today, I think something like 35% of all tournaments/points on offer are on clay, while only 25% of majors are (and if you are someone who includes YEC as a "big 5" tournaments, then it's even worse at 20%).