>>16471398Because if they took the American approach (pic related) they'd divide the fanbase over who's a good protagonist and who isn't. If they were all similar (which they probably are) that defeats the purpose of having different protagonists.
Ash pretty much has a the quintessential shonen personality that every protag would have, so there is no reason to replace him.
Also, there have only been about 800 episodes, so even if you care about the timeline he'd only be 12 or 13. Nothing unreasonable like the audience makes it out to be.