I think it’s the coloring/shade change around the chest. Makes the pecs look saggy.
Yeah. I agree. It's exactly where the two tone is divided, makes it look like a bad fit. The fit is probably fine but the darker tone cutting through 3/4 down the pecs makes it look like Mike has a gut and makes Jay look stringy and small.
Obviously they're both holding a ton of muscle and lean. Shirts are terribly designed.