No I think till 18 will be enough (I know that in some countries 21 is adult age).
Still there is big difference in 13 yo and 17 yo.
To be more precise. As I am author of the game about movie production it is quite obvious with understanding of the film industry between 13 yo and 17.
As I remember myself when I was watching 2001 A Space Odyssey by Kubrick or Blade Runner by Ridley Scott those films was boring when I was around 12... it past many years to understand and appreciate such movies and this comes with life experience and knowledge of medium.
And this is just simple example. What about psychology horrors like Rosmary's Baby by Polanski or classic movies by Hitchcock (13-teens even do not know who he is).
The most statement about my game that is too difficult comes from very young players... because they do not understand some business mechanics, do not have skill of abstract thinking and do not have "life experience".