I agree with all of this. I kind of thought he was overstating the significance of that one play in terms of how it affected the rest of the season. It probably was responsible for losing that game but it's a stretch IMO to go much further.
However, he did bring up a good point that fans typically don't consider but as a GM you have to think about. That is, how his teammates view him.
You say he would have had the same stats which is probably true. But it's possible that had no penalty occurred and they go on to win, his teammates have more confidence in him for having moxy. From there maybe they have more respect and confidence in him as a leader.
It's intangibles like that that can affect things but are impossible to quantify.
