I don't know if Scheierman has established what his role in the NBA will be.
As a spot or movement shooter, he's not consistent enough to make you forget his defensive limitations. It still feels like he's more comfortable with the ball in his hands, but that's just not likely going to be his role on any NBA team.
Furthermore, while spacing and 3s are still very important, the popular trend now is full court pressure and grabbing offensive boards. The Cs themselves made it a preseason point of emphasis to play faster. That change in style favors the more athletic players.
Hauser can't even get on the court right now, and we thought he was an established guy. Partially it's due to his shooting slump, but some of it is he doesn't bring a whole lot else to the table. Scheierman while being a better playmaker/passer, is still in that same boat of needing to be a more consistent offensive threat to make up for lesser defense/athleticism.
Shifting Brown to the primary scorer role has also opened up the defensive stopper spot for Minott/Gonzo/Walsh. Scheierman is obviously not suited for that role, so those minutes aren't really available for him either.
Oh yeah, finally I think Scheierman got on Joe's bad side by trying one too many fancy passes that led to TOs. That probably has also caused his minutes to be on the lower side.