It's true. Sadly it takes strong familiarity with wide range of subjects to be able to point out the biases of omission, and a big name to point it out without attracting too much of dismissive shrugs.

In my opinion, the bias is primarily derived from the bias of the sources Wikipedia uses, with influence by the WP editors being only a secondary influence.

Larry Sanger is an idiot. There's a reason he was kicked out early in Wikipedia's history.

Wikipedia is certainly biased, but in what topics are covered, not the content itself. I think they had an example that the article for the Falklands war was longer than the Congo civil war, the deadliest conflict since WW2.