I think picking the flag up was the right call
The rule was written and enforced to protect players. In this particular game where it was starting to get chippy and obviously a lot of chirping was going on. Calling a penalty on something that didn't have intent would have escalated the game to a whole new level
Say that flag stands, I know if I'm a player and the next time its going to be a close call I'm making sure I get my 15 yards worth