In the acting world, audition announcements often mention "playable age" as a requirement. Meaning, what age can the actor pass for, regardless of their actual chronological age.
Decades ago I used to work on the weekends in a grocery store. A colleague there was a 23 year old girl who didn't look a day over 16.
So for me the answer to the thread's question is that the provider can rightfully put the age on his profile that he can (realistically!!) pass for, not his actual age. We are paying for a fantasy, after all.