Purely semantic arguments aren't helpful to anyone.

The word "bias" clearly has two senses in this context. The original term from signal processing indicates a persistent offset, which got appropriated in politics to reflect the idea of a "lean" in coverage. So now "Bias" means "politically charged in some direction or another".

So you can have a "biased" term ("occupy") next to another biased term ("tea party") in a search. And it's reasonable to call the whole thing a collection of biased terms even though by the original definition I guess you'd say they cancel out and are "unbiased".

Language is language. It may not be rational but it's by definition never "nonsense". Don't argue with it except to clarify.