He got bought out 4 years into his deal, I don't think that's aging just fine. Even that 49 point season you're lauding him for in Columbus still showed significant signs of reduced performance at even-strength, he just got uncontested PP1 time on a bad team. The next season he lost his PP1 spot, his raw production tumbled, and he was bought out after that.
Also considering Tom Wilson's highest goal total in his career would be tired for Hartnell's 5th highest and Wilson's highest point total would be tied for Hartnell's 4th highest - I don't think your arguments regarding "level of presence or elevating" really hold water. Even if you attribute that to Hartnell's bigger roles on the PP than Wilson, Hartnell still edges out Wilson in even strength production (and that's even without the surge in league-wide goals the past couple seasons - Hartnell was peaking during the lowest scoring stretch of post-lockout hockey). And Hartnell absolutely was a
player who was
noticed on the ice even when he wasn't scoring (and s
ometimes right after he did score). To put it this way, I'll be very pleasantly surprised if Tom Wilson ever has a 37 goal, 67 point season like Scott Hartnell did (and hopefully Wilson would have fewer than the 136PIMs Hartnell had that season).