Maybe it would help to look at it from a game designer's point of view. You have 20-some characters, each with dozens of moves. Their moves have a lot of variety to them: some teleport, some shoot projectiles, some can armour, and so on. So you want to have a wide variety of characters with a wide variety of moves and a wide variety of play styles. Now, make the game in such a way that it is in perfect balance, so that no character has any inherent advantage over any other character overall.
That is pretty hard to do, Sir. You can have a a couple dozen people working on the game playtesting it, while they are also coding, doing character design, etc. You can bring in some high-level players for about a week (which is all they got AFAIK) to give some input. Yet, there is only so much you can do in advance. When the game is released and there a million people playing, when there are thousands upon thousands of people putting hours and days and weeks into each character to discover tricks and tech, of course there are going to be disparities that emerge.
If you have two characters with two moves each, it is probably pretty easy to make them balanced. When you have dozens of characters with dozens of moves, mathematically it becomes nigh impossible to have a perfectly balanced game, particularly one that is perfectly balanced upon release. Does anyone have an example of a complicated, intricate fighting game with a multitude of characters that was absolutely perfectly balanced upon release? Aren't the constant patches from NRS evidence that they are trying to make IGAU balanced? Maybe the "philosophy" of NRS is that they would like to have a balanced game, are trying to have a balanced game, but it isn't as easy as clicking your ruby slippers together.