I really don’t think this is a big of an issue as some in here are making it out to be.
It is an issue with in very limited cases, where defenders stack up a runner, stop his forward momentum, and then pushes come in from savvy linemen. But the issue is with officials not during their jobs, not with the pushers. Defense did their jobs standing a ball carrier up and stopping him even if he doesn’t go down. Should be whistled dead at that point.