In my opinion, its a two-horse race for the Hart.
Going into the season, the Lightning knew they were in a position where they had less depth than ever before. Their solution to this problem was to rely on Kucherov more than every before, and he's delivered. Those three Canucks had that incredible start, but Kucherov carried the scoring lead for most of the year. His consistency throughout the year deserves recognition and would be his biggest advantage over his main opponent (in my mind).
- 48 points than his next closest teammate
- Most assists by a winger ever
- Highest % of team scoring
- Highest PPG against strong competition (1.92 vs. top-5 teams, 2.25 vs teams 6-10)
In the first month of the season, the entire hockey world got a chance to see what the Oilers were without McDavid being the best player in the world. What they were was the team that lost to the Sharks. After a devastating start that would've crippled most franchises, McDavid returned to form and lifted their corpse of a team back to life. The fact that they were comfortably in a Playoff spot months ago and not fighting to get in at the end of the season is ridiculous given the state of their division at the time. Everyone knows he's the best player in the world, but this is truly one of the most incredible seasons of his career given everything he's been through in one year. That type of in season turnaround is impossible for mortals. Throw in the fact that he'll hit a Gretzky level assist total and could win the scoring race after starting a month later and his Hart case is extremely compelling in a very close year.
I don't see any advantage that MacKinnon has over those two. He plays with the strongest teammates and doesn't really have any distinguishing stats. If he wins the scoring race it won't be by much. Breaking Gretzky's home scoring streak would have been a strong addition to his case, but I'd personally favour the others more even with that. He has been absolutely dominant on the ice and a top-3 player in the world, but I don't see the level of distinguishing achievements that the others have. The biggest thing is that he was consistent for the entire year compared to McDavid, but that doesn't separate him from Kucherov. He is due for a Hart though and I agree it would be odd for him to retire without one, but I don't think that's an argument that should have any weight here.
Guys like Matthews, Q. Hughes, Crosby, Josi, Pastrnak, Panarin, etc. have had incredible years and won't sniff the Hart, truly ridiculous.