For bodybuilding yes but why are their so many good boxers, kick boxers and other types of fighters, all at lighter weights, but cut and built for combat for sure. They're just naturally smaller so they could never step on the stage with pro's with no weight limits.
I was just looking at the IBF (boxing) ratings and the top in the top 10 boxers from light weight down through jr. flyweight their are only 7 Americans out of 90 boxers under 135 lbs. Most are from Mexico, Nicaragua, Thialand and the other countries that don't produce 250+ lb bodybuilders. Maby its a macho thing but I guess they know even with pro cards they wouldn't make dime 1 competing in bodybuilding. The NPC is full of bb from these countries, at the lighter weights but they know their limitations.