Even disregarding the impact, to assess the bias of the contributors themselves a more precise research, comparative in nature, would be needed. For instance, if one writes articles on parliament members in country X, and 70 % of articles are about males, that’s only biased if the actual percentage of male MP is less than 70 %. The same should be done with all the sources for each topic.

And it’s nothing compared to the systemic bias towards the western and anglo-saxon point of view which writing in English and using (mostly online) English sources encourages, let alone languages less global in nature.