I think there are two different motivations for voting for Sengun vs KPJ. People who voted Sengun most likely believe him, Jalen and Sengun would net the most back in a trade and if one was to go it would be Sengun. It's because people think he actually can net a genuine quality high level vet that can help this team a lot with a high playing time load. For KPJ it's because people think he's most detrimental to the fire development of this team going forward.
They were unquestionably the 2 best players on the team this past season, but Sengun doesn't really fit with what the team is probably going to want to do and that makes him likely to be traded since he does have value. KPJ could be traded, but it's kind of unlikely given that he's a perfect fit with the team both on and off ball and there's just no way you could get a player back anywhere near as good.
I think a lot of teams could use KPJ in a 6th man role, and some teams might be willing to try him as a starting shooting guard. He just doesn't fit on the Rockets because we have a prospect who projects to become an all-NBA player at the 2 and KPJ is unlikely to accept a demotion. It's funny that the same poster who is probably highest on KPJ of anyone on this board (except DD??) is also dismissive about his trade value. Almost enough to make you wonder if that poster just likes arguing with people and "winning" stupid internet games moreso than caring about what's best for the team...