Trump goes on in the transcript: “Look we have people that are chopping off heads and drowning people in steel cages and we’re not allowed to waterboard. But I’ll tell you what, I was impressed by that answer. It certainly does not—it’s not going to make the kind of difference that maybe a lot of people think. If it’s so important to the American people, I would go for it. I would be guided by that. But Gen. Mattis found it to be very less important, much less important than I thought he would say.”
In short, Mattis exposed Trump to a different view of torture—a view, by the way, that most American generals and admirals hold. And, especially if he does appoint Mattis to his Cabinet, he might open himself to that view in making policy. However, Trump has not changed his mind on torture—which, since he enthusiastically supported it during the campaign, means he still supports it now.