He-who-voted-for-Kodos said:
The trick is that the nebulous floating time works better with an episodic comedy like The Simpsons. Less so with a story with an on-going, over-arching plot like Pokemon. I think the most entertaining ways I've seen it referenced are people pointing out things like "Kids today will never know how fat Pikachu was, or what assholes it and Charizard used to be." Or responding to a shipping argument where someone brought up Misty by saying that, aside from the one Togepi episode, she hasn't been around for 10 years, she's not coming back.
Oddly, though, one show did address the vague time issue: Fairly Oddparents. It came out in one of the later specials that Timmy had wished for time not to progress and for no one to question it, so he could stay a kid with fairies forever. By the time it came out, 50 years had passed.
What? Lol! No! Have you ever watched a cartoon series before?
It being something that only works in episodic comedy isn't even close to true. Most animated shows of any type have ageless characters over-arcing plot or not. Teenage Mutant Ninja Turtles have been teenagers over episodes that should have brought them into their twenties easily. Yes they've been rebooted, but the original run was more than enough episodes that they should have aged considerably. That's just one example.
Another example would be any Disney cartoon show ever, Ducktales, Darkwing Duck, Chip n' Dale, Gummi Bears, Tailspin, Kim Possible, etc. Some of those shows were more action than comedy, all had over-arching plot, and all of them had an ageless cast that was always 'right now' with stuff that happened 'back then'.
Some of them do focus more on comedy than action, but it still holds true with more action oriented shows. Tailspin, Gummi Bears, and Kim Possible all had gags in them, but they were more action shows than comedy shows.
Pokemon is actually more like something like Darkwing Duck, where the comedy focus is actually bigger than the action focus most of the time. Most of the character interactions rely on gags outside of the battles themselves, and the gags and jokes often creep into those segments as well.
It's almost universal that characters in action adventure animated shows are ageless, especially when aimed at a younger demographic. This holds true even in shows where there aren't any child characters. No one in GI Joe would ever have retired, Beavis and Butthead would always remain idiots in high school, Kim Possible would always be a teenage spy.
This rule is generally true of Anime as well. With very few exceptions, in long running shows the characters are usually ageless. Often the show's premise doesn't work if they are not. They don't get any older unless the plot needs them too.
Short term aging does happen sometimes, but it's unusual and usually a small increment. Characters might have a birthday or another time marking life event, such as the characters in South Park moving up a grade. It didn't really have a significant impact and that was why it was done. None of the boys will ever graduate or really get any older than their nebulous age range. That's how most animated shows work. Live action shows would do the same thing if they could get away with it, but that's more difficult with live actors. They tend to stretch things as much as they can even then.
The reality of the situation is that exceptions to the rule are the more unusual ones in regard to animation. It's just that most of these shows don't last long enough for it to become apparent, but it is usually obvious that if they ran for long enough the characters would remain in their perpetual status quo and never really get any older outside of maybe a small increment life event episode that has no real impact overall on their apparent age.