Agreed....though you may want to trade him sooner than later if you think he's going to continue to get worse. I agree with others that worse case scenario he's good for regular season success. But why exactly are we chasing regular season success right now? The argument people are making to keep him is the argument to trade him. If the Jazz think he's special and can actually be a building block, by all means keep him. But if you don't think he's that player, it's probably better to cut bait and there are several teams who would value Kessler's contract on his low salary more.
Trading someone like Sexton makes my stomach churn, because you could have huge egg on your face. He could be an all star. Walker has way less variability. You're very likely trading a guy who is in between situation starter and very good backup. Like if he has a higher end outcome and is as good as Jakob Poetl, are we really kicking ourselves because we didn't get premium value in a trade? Even though Kessler is young player, he's kind of like a vet. You know who he is and we've seen both ends of the spectrum. He won't go far beyond what his rookie year was or far below what his last season was.
On top of all of this, Kessler really isn't a Hardy type of big. He seems to be making progress with the short roll/dribble handoff stuff....but he's not exactly a system fit. There are some coaches who LOVE what Kessler offers, but Hardy is not one of them. Circling back to my earlier point, there's got to be a team besides the Jazz who wants him more than us.