I understand where you are coming from, but Maluach has played quite well in the G-League of late. Below is the most recent box score I could find. See link:
Now if you look at a player like Maxime Raynaud, he is three years older than Khaman. I heard it mentioned, I believe pregame, the reason Maluach is not playing is because he is not strong enough yet.
I do wish he flashed more athleticism like Fleming, but a high basketball IQ and measurements can carry a player a long ways. Some of his shortcomings can be traced to not playing a lot of basketball when he was young.
gleague.nba.com