His usage at Duke was not real high and his efficiency would likely decrease a fair amount if he were the key focus of defenses. His assist percentages are not that good for a primary ballhandler. His steal, rebound, and block percentages don't seem to indicate he is some type of lockdown defender.
Mika maintained a strong offensive efficiency with high usage while playing with a bunch of below average efficiency players.
Mika is three years older than Jackson which largely explains why Jackson may have a higher upside than Mika, but I think the argument that Jackson is currently better is very weak and not supportable by any evidence.