It's missing the point, as often seems to be the case here. Steven doesn't want to lose his cool so soon after being a Harbinger, but it's really hard not to be frustrated. The things that make Steven the most upset is the cruelty he doesn't understand.

"Because! You're... You're just saying it's my fault for being sad!"

He forces himself to look away, leaning on his knees again. Lion, still napping off to the side, opens one of his eyes to watch them cautiously. Steven getting upset like that probably means something worth noting is up. Maybe.