One could argue that the non call was a make up effort for the terrible roughing the passer penalty on Chris Jones earlier in the game. It really just boils down to human beings making mistakes. Refereeing is not exactly objective.
The ref was behind the receiver so his view could have been obstructed to see it clearly. If the ball was thrown high above the receiver’s head it would’ve been easier to spot the infraction. Not excusing what happened. Just offering a different perspective than refs favor KC bandwagon that everyone seem to be on.