He didnt stop him. He contested a kick. He didn't tackle him without the ball. The contact was made as both players tried to contest a kick. It happens every week. Its not penalised unless one player is trying to take the other out... if both are contesting the kick it's legal
He did stop him. He knocked him ass over.
Let's use your argument in another context. Billy Slater should be allowed to lead with his feet because he is trying to kick the ball - not the player. Ridiculous right?
Yes, he may have been contesting the ball. But he can't impede another player without the ball while doing so. Him contesting the ball does not make it a free for all. If he had of hit him in the head while contesting the ball, he should still be penalised for a high tackle.
There are 3 scenarios here:
1. You don't know the rules
2. Your bias is so strong that you can't apply the rules correctly
3. Both
Regardless, you're wrong.