It would like to see how the total value is being calculated. Having a Hart Trophy worthy teammate on the ice with you 50% of the time likely isn't being considered in that calculation.
At ES, Kucherov is a net PLUS 15 vs. McDavid being a net PLUS 12.
I’m not sure if quality of team is accounted for in these stats, but Kucherov plays with Point, Guentzel, Hagel and Cirelli almost exclusively (all of whom are having strong seasons), so he’s not exactly hurting, while Hyman and RNH have been snakebite this year with McDavid (and he only plays with Draisaitl about 38% of the time).
As for plus minus, McDavid’s expected numbers are much better than Kucherov’s. While Kucherov typically outperforms his expected numbers, this year he has a point on a smaller than usual number of the goals scored when he’s on the ice which suggests that his teammates are having a better effect on those numbers.
Regardless, you’re just moving goalposts at this point. You complained about McDavid being too high based on his teammate being higher and it’s clear that Dom is ranking all award candidates here purely on his formula’s determination of overall value without any narrative aspects. Whether his method is a good way to measure overall value is another question.