If he were to average 1.75 attempts per game, and made 35% of his 3pt shots, his season scoring average would increase from 15.9 to 16.4.
But what that number doesn't show is the increased open lanes and increased shots for the other Jazzmen.
With Donovan Mitchell and at times Ricky Rubio and Jae Crowder able to get to the rim more easily with defenses spread out to cover a Gobert 3pt shot, I imagine the Jazz would be very much better offensively