It shouldn’t be though. To your point, I understand that Giannis is at his best as a point forward, and Dame as a point guard. But like
@kjironman1 said, there’s no reason those two strengths can’t be used together. Dame operates as a PG using screens to get open looks or drive. Giannis works best driving into the paint.
I think it’s got to be like 90% on Doc Rivers failing as a coach at encouraging the two of them to play off of that as often as possible.
If you had Giannis and Dame in Stotts’ offense you would absolutely see a difference in performance.