Point being, Facebook's audience is majority international and it most of all wants to make money. If you occam's razor this, Facebook is simply presenting people with what they want to hear (a well-proven phenomenon[1]). The report has shown nothing to prove that there is some sort of committee that decides which political stances facebook is going to shove down people's throats, but we know it has MULTIPLE groups trying to increase engagement. The international community believes that the American right is nuts, voila, Facebook selectively presents this as the dominant news. Click, click, click...PROFIT.
[1]:https://www.ted.com/talks/eli_pariser_beware_online_filter_b...)