>>720169589
And you would know that those kinds of decisions are a visual language. He draws them slimmer when they're not serious, and then draws them buffer during fights or displays of power. It's not an accident, it's matching the visuals to the tone. High School Gohan is goofier, so he's drawn slimmer. When he wants to show off powers, then high school Gohan is drawn buffer. even in the image you just posted, Gohan is not especially buff. Just looks more cut, since he drew all the lines of the musculature.
When Saiyan man is drawn, his arms and legs are blacked in, so you can't see the cut. His arms and legs are not that buff.