"Disingenuous" is the most overrated word on hfboards as of late.
"Disingenuous" isn't really the best word to use, so I apologize for that. It does imply that one is being sneaky/trying to misrepresent a situation/comparison.
I can understand why someone who's not a fan of the teams that Yashin or Sundin played for would think that they were players of a similar calibre during their best seasons.
I think it's a somewhat... shallow comparison. Let's go with that. Granted, Sundin is chastised by some because he didn't take the Leafs to the SCF, but he never had a playoffs where he scored zero points or one. Yashin had several. Sundin did end up with 82 points in 91 playoff games and a +2 rating. Yashin had 27 in 48 games along with a -16 rating.
He also beat Yashin every time they met in the playoffs. Additionally, as mentioned, he was a more clutch performer during the regular season as well. He spent much more time killing penalties and didn't hold out while under contract.
Sundin also evolved his game more than Yashin did and was better a more versatile and reliable player.
So if we're just talking about talent, Yashin at his best may have been at or close to Sundin's level, but one was much more desirable as a first line or franchise centre than the other for numerous reasons.
If Yashin had focused more on evolving his game and maximizing his talent than on trying to alter his contract, then he could have truly been one of the better centres of his time, but his flaws were just too glaring to ignore.