Generally the reason that it couldn't be a source was that it was editable by anyone, way before the political bias ever came about. A source that can change on a moments notice isn't valid, viable or useful since it might bolster an argument or statement at the time it was cited, and later on do the exact opposite.

That was wikipedia at its best. Now that's its infected with crazies it isnt something you would wipe your boots with when they were muddy, for fear that some malefic poisonous taint would cling to your feet and inveigle its way up your leg to feast on your soul. That ship has long since sailed. Even innocuous non-poltiical articles are rubbish, the left has no boundaries that will constrain them from infesting everything with madness.