They'll improve by 4-5 wins just by virtue of not having the killer schedule the first 15 games. I don't think they tanked. Even with a healthy Trey, they wouldn't have won more than 4-5 of those games.
Where the real improvement will come is over the last 1 1/2 months. Jazz clearly just quit on Corbin. I won't argue whether he was a good coach or bad. That is beside the point. The team just quit. Everyone knew the plan was to "tank." Trey was about the only one who went against that philosophy. The rest played uninspired, "half-***" basketball.
I don't see Utah making the playoffs; that will require almost 50 wins in the WC. I see them possibly having a season like Phoenix: exciting team, a lot of improvement, but still just a little short on experience in March/April when the games get really tough. I hope I'm wrong, though. Right now the weakest link would appear to be Kanter. If he can bust out, Utah could really surprise. But Exum and Hood are still rookies; they'll struggle.