At a given weight, jujitsu and judo, and I'd guess wrestling as well, somewhat favor stocky people of short-to-medium height: short because it's generally helpful to have a low center of gravity, and stocky because it makes you more powerful for a given height and more resistant to certain techniques. But they're also extremely physically tiring. A few extra pounds might be helpful for one of several reasons, but I'd expect a 500-pound wrestler of normal height to lose more in fatigue than they gain in mass; and indeed, we don't see many competitors at 300 pounds or heavier, despite the fact that heavyweight wrestling starts at 200 and has no upper bound.

(Source: am tall, lanky jujitsuka. I haven't studied wrestling, but I've sparred with a few wrestlers.)