Everyone loses their cool every once in a while. I'd be willing to bet the next day he was changing his tune. It's a clear call. It's not even worthy of discussion. Mahomes was just upset and he focused his attention on that play call, but it was the right call, no question. Mahomes just doesn't like to lose and he lost his cool. He's human. Who knew?
Mahomes called Allen to apologize for his behavior after the game. I don't think the after game frustration was about the refs as much as his crappy receivers that he doesn't want to throw under the bus. Either way he whines all game so him whining afterwards is kind of on par for him.