Wrong.
Last season, Matthews scored 64 adjusted points in 62 games. (1.03 adjusted points per game)
In his rookie season, Malkin scored 87 adjusted points in 78 games. (1.12 adjusted points per game)
This season, Matthews scored 42 adjusted points in 34 games. (1.24 adjusted points per game)
In his sophomore season, Malkin scored 115 adjusted points in 82 games. (1.40 adjusted points per game)
These comparisons feature each player at the same age for the entire season. Matthews and Malkin at 20 years old for the first comparison and 21 years old for the second comparison. However, they do feature Matthews in his D+2 and D+3, compared to Malkin in his D+3 and D+4. But because Matthews has one more year of NHL experience in both comparison, I think that evens it out and makes it more than fair to Matthews to compare these two years. (As opposed to D+3 for each, which would be this year for Matthews compared to rookie Malkin.)
On top of that, points per game will generally flatter players who were injured and played fewer games. The effects of fatigue - both physical and mental - will have a much larger effect on a player who plays 78 games than a player who plays 62.
Adjusted points is a poor stat. The higher PPOs in the seasons after the lockout affected top players more than the rest of the league and scoring was less spread out. Adjusted points suggest that McDavid last year would have only been 4th in scoring in '07.
Matthews was 21st in PPG last year, and his PPG was 84% of the combined PPG of the top 10. In '07, Malkin was 20th in PPG, and his PPG was 84% of the combined PPG of the top 10. So I was wrong because I forgot Malkin missed games, but Matthews's sophomore season is essentially on par with Malkin's rookie year.
I also didn't compare Matthews this season to Malkin in his sophomore season, as Malkin's jump makes it pointless. I compared it again to Malkin's rookie year because of both being D+3s as you suggested. Here, Matthews is clearly better per game, as he's currently 12th in PPG. Though obviously in a smaller sample.
I also have to disagree with the idea that PPG generally flatten with more games. There's no evidence to suggest that's the case, as we see just as many players improve as the season goes along as regress. Matthews was likely not "helped" by his injury, because any time off for rest also comes with whatever affects the injury has once he resumes play, as well as general rustiness. What does happen is that players will regress to the mean over larger samples of games. The problem with Matthews is that he's too early in his career to know what that mean is yet. Last year, you could suggest he would have likely regressed with more games as he had a high on-ice shooting percentage, but he continues to have one this year, so he might just be an anomaly since he creates a lot of high danger chances and has a great shot.
Considering Matthews also never looked the same at the end of the season, I would suggest the injury time didn't have a positive effect on his PPG, and I think he compares favourably with Malkin's rookie year, and despite the same sample size would likely continue to do so this year.
As I said though, Malkin made a jump in his 2nd year that makes the comparison pointless. We can't assume that type of jump from the level Matthews is currently at for any player, regardless of how they compare at a young age.
