Well, yeah.
Even biologically, it makes sense. A man can produce children into his 40's, 50's...maybe even 60's. Women start having trouble bearing kids around late 30's, early 40's.
And from an attractiveness standpoint, women often prefer an older man. Age in men represents maturity, confidence, and the ability to provide. Age in women represents....well, I don't know because I'm too busy looking at younger women.
This doesn't mean that any fat arse middle aged man sitting on his couch is "in his prime." But if you're an older dude who actually takes care of himself and has established some level of success in life, you can extend your "prime" well into your 50's and 60's.