I think it's more of a systemic issue than top-down manipulation. Like, as a hypothetical, they're disregarding some people as being extremist when in reality they have reasonable, representative views. This produces biased results, and people who agree with the results share them because it supports their world view. The shares and new revenue reinforce the companies decision to produce biased reports, and the effect is politicians read these popular reports thinking they're accurate and make policy decisions around them, when in reality they're just a political wish-list.