>>53616724According to the anime Oak is 50, but I honestly highly doubt that's the case for the games. He must be like 60 to 70, especially if him and Agatha are the same age.
Oak's latest appearence in the timeline was I believe Diamond and Pearl, so if he's like 60 or 70 then he's 80 or even 90 in sun and moon.
I like to think he's dead and his cousin Samson Oak is a lot younger than him so they didn't have identical facial features while the two were both alive.
Considering how little Game Freak cares about the timeline anymore I'm sure he'll make an appearence in a Pokemon game set like 40 years after red and blue and fuck the entire timeline up like how Mina did.