It’s strength and weakness. KJ is a solid help defense and he’s decent in transition defense but his perimeter defense is trash. He struggled to guard Westbrick one on one. I’m surprise people don’t see this.
Textbook example of another Rockets player whose ceiling appears to be "good bench player" but is instead playing starter minutes. I like him and I'd keep him around unless some team offers a great return to trade for him, his game is perfect to come off the bench, hustle, and score some easy buckets against second units. I don't like him getting more than maybe 18 or 20 minutes per game and I don't think he's good enough to play against NBA starters.
Realistically, Jabari Smith Jr. has also been bad on defense this year too, which is to be expected. Also Jalen Green. Also Alperen Sengun. Etc. It is very difficult to evaluate defense on a terrible defensive team. We are finally starting to play hard, so maybe we can start to improve and see what guys need to work on going into the off-season. I do believe in our workers and our talent.