Sure, the 2001 version is canon, nobodies denying that. The series you're talking about where they burn out is the 2009 series.
In February 2009, Marvel announced a second X-Men Forever, which began its run on June 10, 2009. The second title bears no relation to the earlier comic.
The series, written by veteran X-Men author Chris Claremont, was a continuation of his storylines for Uncanny X-Men and X-Men that were never enacted after his resignation from the title and Marvel Comics following X-Men #3. It ran as semimonthly as a regular title, set in an alternate continuity of the Marvel Universe.
Alternate universe means it's not canon with 616.
If mutants burned out in 616 and died young, we wouldn't have Selene and Apocalypse, who are both thousands of years old.
Gateway is old as dirt, and seems either slow aging or immortal.
Sinister is hundreds of years old.
See where I'm going with this? Forever is alt U, therefore not canon.
To be honest I don 't think he ages. Reason being is that many individuals who have study him also have come to similar conclusions that he may in fact be Immortal. Also the fact since hitting his prime he has not age a single day. Then there the whole thing about the fact he Romulas plus, and Romulas him self is several millennium old. Then there the here comes tommarrow story line, as well as fantastic force which seems to support this.
However I agree he can be killed however, I simply don't believe age can kill him, as long as he has his powers.
However even if his body dies his soul reincarnate so in the purist of senses he truelly is immortal all across the board. He technically from as far back as the ice age.