What transpired was unfortunate but I didn't see Haas purposefully use his body weight to make the tackle, I saw him fall over the player because of the direction and speed he was running in. When a ball carrier is moving forward slowly to make post contact meters and a defender is being dragged along and decides to use their weight to drag them down, I can understand a penalty/sin bin. However, when a player is running full tilt (RCG) and a defender is running full tilt (Haas) and the defender happens to land on the back of the ball carriers legs, I deem that an accident; an accident that has been happening for 100+ years.
I appreciate some will see it differently, but I base my opinion off the speed at which the RCG incident took place and I do not believe Haas had to time to make a conscious choice to do anything with his hips/legs. If anything, RCG caused Haas to fall and land where he did because he was attempting a 'spin' out of the tackle to crash over the line.