Some profilers don't include their age, or even hints in general. Then there are those who specify very narrow ranges of preferred ages in a partner.
Does it matter?
Just in terms of kink play and scenes, probably not so much. Sure, there are D-types who want some young hardbody, and there are subs who are turned on by on some steely gray on the temples, but generally hot arousing play in scenes can be had over most any age range. As long as the power dynamic is crackling, any two (or more at times) healthy partners can fully savor D/s or BDSM consensual play.
It is in the more vanilla parts of the connection that things can unravel fast. Take music-- every generation is raised on sightly different vibes, and sometimes a two or more decade difference can make one partner's tunes the other's pure static. The more in person and closer to 24-7 the relationship is, the harder to resolve such things.
This musing came to me today, on 9/11, after a news person pointed out that a significant percentage of us were either not born or too young to have any memory of that horrific day. For the rest of us, it is an apocalypse in our background we all share, like Pearl Harbor Day for our ancestors or older parents. With too great an age spread, 9/11 for a younger partner is just something read about or a disaster clip.
So, at least for this Cage elder, having ages posted in profiles is of value more for cultural or musical reasons than for any D/s potential reasons.
Okay, if you are of a curious mind and are itching to ask -- I do prefer mature minds, and the wide variety of more mature bodies, despite what gravity and living may have done to alter them over time!