Rarely does it look like a clear "debank X" system; it's more like "you look suspiciously like someone who might use our systems in a crime, in a way that will cost us money and get in trouble with the law, so we're not going to touch you". Which is much harder for an innocent person to deal with.

I do think there ought to be some sort of fallback banking and account denial review process, if we're going to make it that critical to society.