I understand why the flags came in at the end of the game & not before: With the Bengals up by 4, a FG wasn't enough, so the Rams had to go for the TD. Since the Rams were running out of time the Bengals decided the best strategy was to hold on every play with the intent of doing everything necessary to stop the Rams from getting the TD. Since they were obviously grabbing jerseys (all the replays showed the fabric stretching in the hand of the defensive players) the refs understood the Bengals strategy & could no longer just let them play. They had to call the penalties.

I'm a Bills fan & I can give you two examples from this season. In the Bills Tampa game the Bucs held Diggs in the endzone & no call was made in the final part of regulation. Bills fans went nuts because it was obvious that Tampa got away with a strategic penalty, which in that case wasn't even called. In the famous 13 second KC playoff game the Bills coaches were criticized for not taking holding penalties at the line of scrimage at the end of regulation.

Years ago I was at a Bills game vs the 49ers. It was at the end of the 1st half & the 49ers just kept getting pass interference calls until there was only enough time left for the Bills to kick a field goal before halftime.

Since everyone knows this strategy late in games/halves is deployed to keep the opponent from getting a TD, the refs have to respond with greater vigilance at that point in the game. That's exactly what they did & it was the right thing to do. The Rams overcame it with a quick pass because they figured out what Cincy was doing too.