I don’t think there’s a very clear answer. They’re the consensus top 2 in the league, similar age, career achievements and late bloomers. Both relatively injury free so far though Jokic is more available, both seem intent on staying all or most of their careers with their draft team.
Personally, I think it’s harder to build a team around Giannis you’re going to need people to compliment his weaknesses in shooting, free throws and late-game situations. Jokic dosen’t need as specific tailoring of teammates to his skills so your team might be more consistent through roster transitions. I guess you could knock Joker down for his defense but finding a power forward like Gordon who can cover up a bit on defense is easier than finding multiple good shooters.
Secondly, Joker’s game atleast appears like it’ll age better because it’s more IQ and finesse than athleticism. That might change if Giannis develops his game with age like Lebron did but it’s a less certain bet than Jokic.
If this was a legitimate redraft using current GMs I wouldn't be surprised to see Luka or maybe Tatum get drafted ahead of one or both.
Luka is 4 years younger and probably the most marketable player this side of LeBron. Not to mention he is an absolute freak, as is Jokic and Giannis. Tatum only like 18 years old too.
On paper I see why the seemingly obvious choice for 1-2 would be Jokic and Giannis. But factor in everything else I could see a business minded GM, particularly in a big market, getting rambunctious.
Personally if I'm strictly hunting wins I'm going Jokic.