Non-lawyers often seem to misunderstand this phrase. "Innocent until proven guilty" is a statement defining the fact that in criminal cases, the burden of proof rests with the government. They have to present evidence proving your guilt beyond a reasonable doubt; you don't have to present any evidence proving your innocence beyond a reasonable doubt.
That's all it means. Obviously judges are not supposed to come into a case assuming you are guilty, but you can say that about any type of case. The phrase certainly doesn't mean we have to pretend that you are perfectly innocent up until the point of verdict.