The Tush Push should have remained an illegal play

I don’t remember exactly when the rule was changed, but at one time, it was illegal for a team mate to push another player forward.
The QB last night was stopped, all of his momentum was ended and he was simply laying on the pile. Then instead of blowing the play dead at this point, teammates are allowed to push the pile. In essence, a team is allowed to run two plays in one. The first play was stopped and failed, the second eventually scored.
All of the timing is left to the discretion of the ref. It’s ridiculous.