Time is a funny thing in Fox’s X-Men movie universe. X-Men: First Class takes place in 1962, and Dark Phoenix takes place in 1992, yet the X-Men barely seem to have aged in all that time. If these movies didn’t make a point of anchoring themselves to specific events in world history, you’d never know the current series takes place over the course of three decades. And don’t even get us started on the future timeline seen in Days of Future Past…
To highlight just how weird the aging process in the X-Men movies has become, we’ve put together a slideshow comparing the cast of Dark Phoenix to how they looked in their original appearances and how they’re supposed to look in the era of the classic X-Men trilogy. Apparently Wolverine isn’t the only mutant who never ages…
Source: IGN.com Dark Phoenix: Why Don't the X-Men Ever Age?