Having trained hundreds of Pros over the yrs, one thing is for sure.. age, within some limitations, does not preclude the possibilty of becoming a Prof.
It may limit one from the competitive arena, but should not from a teaching aspect .Even that is poss. from a Pro/Am category.
In addition, the " style " you choose to commence that journey, can make a big difference .
For e.g... if you choose Amer. style, then the Bronze ( first level ) is a little less demanding physically than the Intern. style, but... the downside is, there are more dances to " master " .
You may eventually decide to qualify in both styles .Its a "time " thing.
I would advise to investigate which Soc. you wish to be examined by ,and then check what their requirements are .
AS to the comment that you cannot make a living teaching dance, well, that depends largely upon your location, and the style you choose to teach .
I would concede, that there are less male students than female, when one examines the typical ballroom scene. However.. there are areas which are more evenly divided from a teaching standpoint.. for e.g... Salsa and C and W ,and possibly WCS.. that, of course, does limit ones variety .
In the " chain " school setting,generally, there are also more opportunities for female teachers. They seldom take on board people to train,that they are unable to use .