A well-trained judge can tell the difference between apple-like ester and acetaldehyde. But only a minority know the former as ethyl hexanoate, and even fewer will refer to it as such.
I think that a good judge provides useful feedback. It's true that a flavor might be ethyl hexanoate, and not acetaldehyde, and we know the difference- but it's not at all helpful to not tell someone that, unless you also tell them what THAT means, and how to fix the beer that is flawed. Big words do not a great judge make.
One thing that I"ve discovered over the years is that I don't really like wheats, sours, or Belgians all that much. But I am a great judge of the styles I don't love. Part of that is simply because it's easier to deconstruct a beer that I don't love- does that make me biased? No, I don't think bias comes into it. Bias would be if I know my best friend brewed a certain beer, and I chose to pick that one over another beer that is better or equally good.