This didn't use to be the case, I recall having Joe Thornton in HockeyAllsvenskan, aka. Swe-2 because all his attributes had dropped so low that he was fine to play there.
I'm going to use a 40 year old Tavares from my current 1.4 save, and Bobby Ryan from an older save to illustrate the difference:

Apparently getting old makes your hands smoother, your shot harder and your ability to get open better.
Meanwhile in old patch territory:

Getting older just sucked!
So what does the point production look like in the new patch?:

That looks pretty fishy, what about in the old patch?:

Considering how huge this change is I'm surprised it's not being discussed more. Especially since it's complete and utter nonsense that losing your legs makes you a better player; I'll agree the old patch behavior was far from perfect, with players going from a god to useless in about a year. But every single top 6 player playing until they are 40 without any drop off in ability is hardly an improvement.
And this isn't just happening to top tier players like Tavares, Val Nichushkin is still playing top line minutes at 36 despite being at 6-7 physicals across the board. These old players who refuse to decline and retire clog up the AIs top lines so their younger players never get a chance ever. They will play old no-legs over their high 1st round drafted scorer until no-legs force retires at 40/41 depending on how you want to count it.