If Giannis will win another championship, then I will have to admit that he is already in level with Lebron James and Kobe Bryant, for now, there are people who are still in doubt that the Bucks will not win a championship if they face a healthy Nets or a healthy Lakers/Clippers in the NBA Finals.
Those people that are in doubt of Bucks didn't managed to see their progress through all of these years when Giannis gets in. Although it's not necessary at all but you get to see what they've been for the past years.
And if Giannis wins another title next season, comparisons will be made for sure but it will always be Giannis as him and the same from LBJ.