It's the quest for "engagement" and getting always more users and ad views that generates this situation. What can be used to sell you shoes and earphones can also be used to sell you political ideas. When the algorithm wants to show you some inflammatory and misleading political factoid because it knows that it's very likely to make you react, it's working as intended. Not because it was written by a communist, but because it was written by somebody optimizing for this metric.
As a counter example: do you think HN manages to remain mostly not completely trash because it's run by apolitical people or because it's effectively run not-for-profit? I think I know the answer to this question.
It's amusing how I've seen this "internal politic" boogeyman pop up in discussions over the past month or so. As if all the woes of the silicon valley could suddenly be blamed on those pesky "woke" devs while everybody else just tries to get the job done. This American election can't be over soon enough, everybody seems to be losing their marbles.