I think the 'unexpected' things that Bruno showed in the workout include his passing and his mid-range shooting. He's got some skills, and he has a few offensive moves from mid-range that are comparable to Deandre Ayton (though Bruno is a couple inches shorter). Combine that with the fact that Bruno has a body and athleticism that's almost on par with guys like Derrick Favors, young Dwight Howard or Alonzo Mourning, and yeah, he's a nice prospect. His problems seem to have been his awareness on defense in certain situations, but Kabengele gets some of the same criticism.
One way or another, the Jazz are going to lose Favors within a year, and they may be willing to draft a big. It's probably not their first choice to draft a big, but I think the Jazz like both Bruno and Kabengele. There's a good chance that one of them is available at #23. I think they're probably intrigued by Claxton too, but he's so raw that he's more of a project.