He singlehandedly took the Mavs to the finals last year. The Mavs won't be better Anthony Davis, and they will sink in the standings from this point on.
Last year Doncic was #3 in the MVP race, and right now he is #4, but could still win it.
You think the Mavericks traded one of the best players in the NBA because he's not that good?
Your argument is insane. Why do you think Mavs fans are screaming. They had a chance for the finals, and now they will spend the next 5 years rebuilding. They are a manifestly worse team.