Based on comments after week 1, I think this is a coaching decision more than a Trubisky decision.
https://www.espn.com/nfl/story/_/id/34591576/mitch-trubisky-says-pittsburgh-steelers-offense-needs-killer-mindset
"When our defense gets turnovers, we need to turn those into points," Trubisky said. "That's my mindset. And that's what we're thinking about when we get the ball taken away, we've got to turn it into touchdowns and not just field goals."
"With downfield throwing comes the potential of negativity and turning the ball over," Tomlin said.