I mean...he could absolutely get better. He could stay stagnant or simply be who he is. An inconsistent player who will have some big games and some big catches but will lose focus during the year as well. We could do worse than 830 yards and 7 TDs, but we could also improve on it...
Perhaps they think he can improve at focusing better throughout the season as it was his first shot at a larger role on offense.
That being said...I think we need a more dynamic player at that position. Gabe is fantastic as a deep threat and catching the ball along the sidelines, but he doesn't get separation. I say he plays as a #3 next year and then gets replaced the following season. Even if he starts as the #2 but then starts ceding playing time to the rookie as the year goes on as he gets more comfortable role, I would be fine with that.