I think it's almost guaranteed that this model has race-related biases, so no, I don't think you're kidding at all. I think it's entirely likely that an Asian (or white) kid of the same build, wearing the same clothes, with a crumpled-up bag of Doritos in his pocket, would not get flagged as having a gun.

Using humans for training gurantees bad outcomes because humans cannot demonstrate sociality at the same scale as antisociality.