David Sirlin wrote on this topic in his book:
[details=Spoiler]Many versions of Street Fighter have “secret characters” that are only accessible through a code. Sometimes these characters are good; sometimes they’re not. Occasionally, the secret characters are the best in the game as in the game Marvel vs. Capcom 1. Big deal. That’s the way that game is. Live with it. But Super Turbo was the first version of Street Fighter to ever have a secret character: the untouchably good Akuma. Most characters in that game cannot beat Akuma. I don’t mean it’s a tough match–I mean they cannot ever, ever, ever, ever win. Akuma is “broken” in that his air fireball move is something the game simply wasn’t designed to handle. He is not merely the best character in the game, but is at least ten times better than other characters. This case is so extreme that all top players in America immediately realized that all tournaments would be Akuma vs. Akuma only, and so the character was banned with basically no debate and has been ever since. I believe this was the correct decision.
Japan, however, does not officially ban Akuma from tournaments! They have what is called a “soft ban.” This is a tacit understanding amongst all top players that Akuma is too good to be played, and that he destroys an otherwise beautiful game, so they unofficially agree not to play him. There are always a very small number of people who do play him in tournaments, but never the top players. Usually a few poor players try their hand at the god-character and lose, which is utterly humiliating and crowd-pleasing. This is an interesting alternate take on the “hard ban” we have in America.
That’s all well and good, but Japan has also shown signs of a soft-ban on another character in Super Turbo. I bring up this example because it lives on the threshold. It is just on the edge of what is reasonable to ban because it is “too good.” Anything less than this would not be reasonable, so perhaps others can use it as a benchmark to decide what is reasonable in their games.
The character in question is the mysteriously named “Old Sagat.” Old Sagat is not a secret character like Akuma (or at least he’s not as secret!). Old Sagat does not have any moves like Akuma’s air fireball that the game was not designed to handle. Old Sagat is arguably the best character in the game (Akuma, of course, doesn’t count), but even that is debated by top players! I think almost any expert player would rank him in the top three of all characters, but there isn’t even universal agreement that he is the best! Why, then, would any reasonable person even consider banning him? Surely, it must be a group of scrubs who simply don’t know how to beat him, and reflexively cry out for a ban.
But this is not the case. There seems to be a tacit agreement amongst top players in Japan–a soft ban–on playing Old Sagat. The reason is that many believe the game to have much more variety without Old Sagat. Even if he is only second best in the game by some measure, he flat out beats half the characters in the game with little effort. Half the cast can barely even fight him, let alone beat him. Other top characters in the game, good as they are, win by much more interaction and more “gameplay.” Almost every character has a chance against the other best characters in the game. The result of allowing Old Sagat in tournaments is that several other characters, such as Chun Li and Ken, become basically unviable.
If someone had made these claims in the game’s infancy, no sort of ban would be warranted. Further testing through tournaments would be warranted. But we now have ten years of testing. We don’t have all Old Sagat vs. Old Sagat matches in tournaments, but we do know which characters can’t beat him and as a result are very rarely played in America. We likewise can see that this same category of characters flourishes in Japan, where Old Sagats are rare and only played by the occasional violator of the soft ban. It seems that the added variety of viable characters might outweigh the lack of Old Sagat. Is this ban warranted then? To be honest, I am not totally convinced that it is, but it is just barely in the ballpark of reasonableness since there is a decade of data on which to base the claim.[/details]
Dunno how accurate this is, or whether this information still is correct to this day. Still, it’s clear O.Gat’s not really softbanned for his power level alone.
Claw is also softbanned iirc.