LeBron James is always going to be LeBron James. He doesn't need trash talk in order to take a game over.
That being said, one fan pointed out that Paul Pierce may have heckled James, leading to the Game 7 comeback and an Eastern Conference Championship for the Cavaliers. The video is quickly going viral as some Celtics fans are looking for a reason or someone to blame.
It probably didn't make much of a difference but fans will always speculate.