The answer right now is Panarin. Maybe Kucherov will regain his Hart winning form and re-establish himself as better than Panarin. But right now, while Kucherov is out for the season, Panarin is at 120 point pace. Panarin's pace both of the past two seasons is higher than Kucherov's in any season except his Hart season in 2018-19. Kucherov still has the higher peak, but until he's back Panarin has to get the benefit of the doubt for being clearly better over the last two years.
What you're saying may be factually right - but another statement I could make would be:
Kucherov has been better in every single season, and every single playoffs head to head against Panarin his whole career (minus that 4 game playoff sweep) - except for a the month of December in the 2019-2020 season, where Panarin scored 22 points in 14 games, and Kuch had 13 points in 14 games. At the end of that season - Panarin had 10 more points than Kucherov in 1 more game played. It's all tied to that one month of extra production, in December of the season.
I'm not saying we shouldn't count December - but outside of that:
Kucherov outscored Panarin from January 1st on last season
Kucherov outscored and outplayed Panarin in the playoffs in 2020 (led playoffs in scoring)
He's not playing this year, so can't do a head to head comparison
Panarin was pretty good in Columbus in 2018-2019, but Kuch had 128 points and swept the awards
Kucherov was also better in the 2 seasons prior
I think you give Kucherov the benefit of the doubt here - that upon his return he will continue to produce at an equal or above level than Panarin as he has his whole career.