It's been said, but I'm going re-state and agree with the idea that it's probably best to judge person by person and depending on their background.
I've also seen it stated that someone can't become a competent lancer/drg in 5 years. Obviously there are no dragon slaying, mile high jumping dragoons in reality, but there are people that pick up a weapon and in 5 years are competent enough to be called a master, if only a lower tiered one. There are also people who do this at a pretty young age, even now-a-days. I don't think it's beyond reason for a person younger than 24 to claim mastery of dragoon-ing.
There are obvious exceptions, including, but certainly not limited to, the possibility that the ranks of the dragoons don't accept people that young or the character themselves is not originally from Ishgard or has some tie there-in. I personally think the biggest thing that ought to limit whether a character can claim to be a master level dragoon is whether they would have had the opportunity to be exposed to the art, rather than something like age.
I've also seen it stated that someone can't become a competent lancer/drg in 5 years. Obviously there are no dragon slaying, mile high jumping dragoons in reality, but there are people that pick up a weapon and in 5 years are competent enough to be called a master, if only a lower tiered one. There are also people who do this at a pretty young age, even now-a-days. I don't think it's beyond reason for a person younger than 24 to claim mastery of dragoon-ing.
There are obvious exceptions, including, but certainly not limited to, the possibility that the ranks of the dragoons don't accept people that young or the character themselves is not originally from Ishgard or has some tie there-in. I personally think the biggest thing that ought to limit whether a character can claim to be a master level dragoon is whether they would have had the opportunity to be exposed to the art, rather than something like age.