Disagree. Almost all his issues are on the offensive side of the ball. He was the bench leader and took on a huge usage rate because he could dominate physically. Much of his perceived low IQ is also offensive related because of not having a left hand, being very aggressive, and playing in a system that promoted bad habits, meaning the coaches rolled with it because he got to the free throw line at a high rate and hit 80% of his free throws.
Defensively, he actually has instincts that are hard to teach, as he operates like a free safety and can close passing angles that others can’t anticipate nor get there in time like he can due to elite physical attributes.
So, what I think people get wrong about Eason is expectations. Scalability is crucial here. In the NBA, he will play early because of his insane defense. On offense he will stand in the corner and hit open 3s. The last half of the season he hit over 40% from deep. His offensive development will be long and slow like it is with many Spurs players, and he might not ever get there, but you will never have to worry about motor and effort, unlike Luka and Lonnie, two busts because of that exact trait.
I see him as undervalued and again scalability and expectations are the key.