I would say Mariah looks goods, but I preferred it when she had dark hair. Also, I don't know why the phrase "for her age" is added, she's hardly a geriatric! Are women in their 40's not expected to look good?
I think it might be because it gets harder and harder to keep looking good as you get older. Of course, celebs have lots of money at their disposals so they can easily cough up on plastic and/or cosmetic surgery and there's no denying that that helps (as long as they don't go OTT with it).