Maybe he is just showing off one side of his basketball skills? He is not known to be a playmaker, of course he is more of a shooter, but with Klay taking the shots outside, maybe Steph just think of becoming the point guard in this game. For sure if this is a close one, the complexion will be very different as he needs to score and help Klay. Let's watch Draymond next game, they need his presence in the middle and the energy he can bring to the team.
It wasn't really mainly about him getting his playmaking out, it was more about getting out of the way for Klay, there is a difference between the two. One of them means that you are going to end up with a great teammate and just not do anything to block him and just let him be, on the other one you are one of the reasons why your teammate is great. Stockton didn't just let Malone score, he helped him score. Step just got out of the way for Klay, not help him out.
It wasn't a "bad" game by step neither by the way, I mean sure he didn't do much, but he did what he was suppose to do in this game, if you would help your team by not shooting much, then you stop shooting and let others do that (something westbrook needs to learn).