You can’t compare their rookie seasons at all, it’s like comparing Apples to Oranges in the way they were used, playing experience before they got in the NBA, etc. Based on measurable alone Giannis with his skills and potential skills has the higher ceiling. He also is good on both sides of the floor, while Mitchell we have yet to see if he will be a better defender or not. If you ask anyone in the NBA who they would build their franchise around for the next 10 years, everyone including even Jazz personnel would take Giannis.