I'd take SGA over Giannis for the same reasons i'd take Jordan over Shaq. i.e. 3.5 quarters of dominance is great but the limitations of being unable to shoot, make freethrows, or facilitate in clutch time isn't worth the 2x more defensive rebounds over the course of the game. Shai actually has a higher TS% than Giannis last year, and so did Jordan's best years compared to Shaq's best; so scoring (ppg and efficiency) favored the guards.
So what does that have to do with Jokic? He provides the production of those bigs but without any of the deficiencies in being unable to shoot, hit freethrows, or facilitate in the clutch. I think Jokic vs Shai is closer bc (1) i don't think stat generating heliocentric playstyles are the be all end all (see 2017 Russ), and (2) something does need to be said about the defensive end of the floor.
So for now i'd put 1. Jokic/Shai and 2. Giannis.