Walton runs a read and react offense. He expects his players to read what the defense is giving them and setup the plays accordingly.
Which works well for veteran teams or a team with a high basketball IQ. That is why the team started clicking when he started the 5 highest BBIQ players right before the lockdown. Fox, Bogdan, Giles, Bjeli and Barnes. Which is why Buddy came off the bench. Why he went away from Giles in the bubble may be why the Kings flounder their chance at the playoffs and cost Vlade his job.
The role of the GM would be to give the coach the players they need to run their system. The problem being that Bagley will probably need to really increase his BBIQ, since he will likely start, for the Kings to be successful next year in Walton's system.
BTW, if Walton retains his job, I would really be in the new GM ear to bring back Bogdan and Giles. They fit his system for high BBIQ players he will need to succeed.