You asked why. That is why. It's not just one thing, but if you're looking for the most impactful specific, the goaltending we've faced in the playoffs has been drastically different than both the goaltending we've faced in the regular season, and the goaltending teams generally face over an extended sample in the playoffs.
We've struck a good balance between giving the team a chance in our best years, while not depleting our stocks.
It wasn't his best series, but he was still one of our best players.