Not sure where it is, but I remember an interview or something (within the last few years) where he admitted that trading Johnson was a mistake and he learned after that, that you have to be willing to pay big when you are pushing for a title.
Did Sarver also learn than he is not the General Manager? He is learning on the job. Our GM is learning on the job. Most of our (many) recent Head Coaches have learned on the job.
So far, Sarver hasn't learned very much. Hire inexperienced "yes" men without the credentials to fulfill their responsibilities, so Sarver (the attention getter) can play his ego games.
Trading Johnson was a "mistake", but not allowing basketball people to make the personnel decisions was a bigger one. Has that changed? I think not!