When the rule was changed in 2006, it was a near-unanimous vote. That is not common in rule proposals, everyone was tired of the issue:
“What the league found was so difficult was you never were sure who was pushing who,” said Mike Pereira, the former NFL director of officials who became the rules analyst for Fox. “So you’re not necessarily pushing the runner. You could be pushing someone else that’s in contact with the runner. So it became really too difficult to officiate. Therefore, we just said, ‘OK, it’s legal to push.’ ”
https://www.latimes.com/sports/story/2022-12-30/pushing-the-pile-nfl-rule-officiating
They’re having an identical problem with pulling the runner. Neither pulling or pushing have been flagged since
The last time helping the runner was called at the professional level was in 1991, when
Kansas City Chiefs center Tim Grunhard pulled
wide receiver Robb Thomas in the divisional round of the playoffs.
https://en.m.wikipedia.org/wiki/Helping_the_runner
So much so that they’re not even bothering to enforcing pulling the runner more even though that’s still a penalty, despite it not being called in 35 years