Pixar's Inside Out (2015)
Despite the fact that short men are statistically less aggressive on average, we often see short male characters being stereotyped as angry in fiction, even in children's media. At best, the intention is for the character to be laughed at, at worst to be disliked. Either way, the reason is that a mad short person is not taken as seriously, and short people are also not allowed to display as much aggression. A tall male character displaying rage would not be considered stereotypical, nor as comedic.