>>40020714Ash is both a legacy character and a good POV char for Japanese boys. The executives wanted him to stay amd promote all games forever because of how marketable he is. They were afraid that him winning a league and coming closer to the Champion's League would be detrimential to their advertisement strategy and kill the series' "watch from whichever moment you want" factor.
This is also why every protag after Brendan was a Discount Red/Satoshi Clone #N, to the point that anime started using their clothing for Ash.
Basically, the studio convinced execs that in the age of Internet, with easier ways for watchers to get feedback or start boycotts, it's easier to let Ash win leagues and somehow write around that, still promoting the new games, while letting old-timer fans see their long time wishes come true.
