This. I never felt it was a penalty when I saw it live. And still felt that way when I saw the replay.
For starters, the puck was not on his stick when he was pulled down. Though he probably would have picked up the puck and carried it in, but at the time he did not have possession of it.
I also didn’t feel he had a whole step on the defender, though I could be convinced otherwise.
Finally, he was near the side, not down the middle. So it could be argued at the time he was pulled down, he didn’t have a clear scoring opportunity.