I believe it wasn't that long ago the NFL didn't allow you to push your own teammate / ball carrier. You could hit and push a guy trying to tackle him, but you couldn't basically get behind and push your own guy forward while he was carrying the ball.
Would be fine seeing a return of that...
They sure didn’t - and that wasn’t all that long ago, even though the example I’m going to give happened almost 60 years ago. Remember the famous play that ended the Ice Bowl where Bart Starr scored on a QB sneak? There’s a great picture that shows Starr scoring and RB Chuck Mercein with his arms in the air, apparently signaling a TD. The original play call was for Starr to hand the ball off to Mercein, who per the plan, would score the game winning TD. When they lined up, Starr noticed a gap between the C and RG and decided to keep it himself on a sneak - he’s the only one who knew what he was going to do. Mercein ran hard to the line expecting to get the ball. When he saw Starr keep it and was about to score, he threw his arms up in the air to show the refs that he wasn’t giving Starr a push.
I’ve said a few times that I hate the tush push and am hoping the NFL does the right thing, and makes it illegal. There seems to finally be a “push” (pun intended) in the NFL to make it illegal - helped along by all the penalties on the Commanders in the NFCCG.