I don't know if I'd go so far as to say that it is the determinative factor, but it certainly is an indicator. Their role is to look out for the players, keep them healthy and extend their careers, and the argument is that the "hip-drop tackle" puts the players at risk. Which, yeah.... it does. It's a violent game.
This is one of the ways I was taught to bring down a big running back with a head of steam when I was a linebacker, if that's how I had hold of the dude. If they ban that tackle, it's going to be one more rule that's subjectively and arbitrarily enforced, and people will be even more pissed at the referees. Teams will make a stop on third down and see it turned into a first down with a stupid and controversial penalty. and everyone will be on the warpath.