Based on what?
Trey hit a couple of fourth-quarter shots and suddenly everyone gets weak in the knees? Other than those shots, he had a ^&%$# year shooting-wise. OK, you can say PG's generally struggle in their rookie seasons. But the fact remains that Trey is a small PG who lacks speed. He ain't gonna grow during the summer, nor will he get much faster. Yes, he'll get better. But he'll always have considerable limitations. Trey can become "crafty" but he'll never be great. He just doesn't have the size and strength to outmuscle or post-up other PG's, nor the speed to blow by them. My hope is he becomes a top-15 PG in the league, maybe even in the discussion as 10th or so. But he'll not get beyond that.
As for team potential, I agree the Jazz don't have any superstars. But I disagree that we don't have potential all-stars - Hayward, for one. He was misused this season; take away running the offense so much and his shooting will recover. There's a reason he gets invited to the national team camps. Burks can be unbelievable if unleashed. Kanter and Favors are making progress. And add in our pick wherever it falls. Maybe I'm wrong and a new coach will make zero difference. But I don't think so.
I think the Jazz will have a pretty decent 7-man rotation just with their current five plus two first-round picks. Add 1-2 FA's and Gobert...that's not a bad group. Probably too young to make the playoffs next season in a tough WC. I'm projecting about 40 wins. But in two years, I see them making the playoffs, then pushing for home court after that.