The absolutism you espouse wrapped up in guilt by association exemplifies the problem - if that was your intent, bravo.
At best, someone could use it as part of an adversarial process at arriving at the truth, but the author doesn't do that. They take the definition at face value. (A ridiculous definition at that).
I wouldn't use PETA for my definition of factory farming.
So yes, if you aren't able to find a non-partisan definition , then I assume the whole piece is partisan, and therefore lacking credibility.