A bit late on the whole topic of Pokemon masters, but I reckon I can still throw in my input on the whole thing :p
Basically, I feel like there's no real definition of a Pokemon master, and that it's entirely up to each individual to decide what it takes to become a Pokemon master. I reckon the original requirements were to simply become the champion and catch 'em all, but the entire franchise, the entire concept, basically everything about Pokemon has expanded immensely since R/B/G/Y, so there's no longer really any set definition on what a Pokemon master is, and the only reason someone like Ash is chasing that goal, is because that was his dream from when there actually were set requirements for him to reach to actually become one. But now they're just holding onto it, because it'd make no sense to change his goal. Meaning Ash will be forever stuck roaming around the world, trying to achieve something he doesn't know how to become ;) Well at least that's my bet.
But as for whether Red or Ash could be considered Pokemon masters; there's multiple things you'd have to take into account. First of all, how does one become a Pokemon master, which I've already explained my opinion on. Second of all, have any of them even reached what the (supposed) original definition of a Pokemon master is. We know that Ash definitely hasn't caught 'em all, and in all honesty, it doesn't really appear to be that high priority to anymore, so if catching all Pokemon plays a role in whether or not one is a Pokemon master, he definitely isn't one. But when the list of Pokemon keeps expanding every few years, I think it may be a bit too much of a requirement anyways :p But what about becoming a champion? So far, the only competitions he's ever really succeeded in are smaller ones scattered around the region, the Orange Islands league, and of course the Battle Frontier, while ranking pretty high in all the league tournaments he's taken part in. And while beating the Battle Frontier is quite a big feat, could he really be considered a champion through that? Again, it's up to each to decide on that in my opinion, but it can all be cut pretty short by pointing out, that if becoming a Pokemon master is actually his goal, he mustn't have reached it yet, if he's still out there travelling around :p
As for Red, it's both kinda hard to say, and kind of not. I mean, looking at it one way, the Red from the games definitely became a Pokemon master, since he became the champion and caught 'em all, but really, we were the ones who were controlling Red, and one thing there's always been huge emphasis on within the Pokemon games, is for players to continue the battles with their friends, to determine who's the best. And that's really a neverending battle, meaning the title of Pokemon master never really stayed with one person. Again, it's kinda tough to say, and really up to each to how they wanna interpret it, so there's not really a simple conclusion to this.
The NPC version of Red never really continued past Johto either though, and as he was defeated by the player in G/S/C and HG/SS anyways, could he really still be considered a Pokemon master?
All in all, personally I don't really believe either of the two could be considered Pokemon masters, but I feel like that's up to one self to decide, since there's not set definition on what a Pokemon master actually is :p
