This doesn't answer your question specifically, but there's the possibility that FB wanted a heated political environment inside its platform so it could sell more ads for all parties involved in the race, keep people engaging with the platform, etc.

Everyone wanted a different outcome. All of the monies accepted by NRA and other right wing organizations would not have been investigated if Clinton won in 2016. Trump would have averted the whole issue of finances and set himself up to create a new right-wing media organization. Chaffetz and other politicians admitted they had "years of material" on Benghazi with which they could hound Clinton. All of the potential money laundering operations through the RNC would have gone unnoticed. Facebook would have enjoyed years of elevated activity with political arguments.

But because of how things played out, we slowly became more introspective and started questioning. Scandals involving sexual impropriety with actors, culminating in the #metoo movement, is part of this introspection. And there will be increased scrutiny in social media and its role in enabling the current situation.

CA may have created retargetting lists and segmented users out to create target lists and lookalike audiences.

That's one of the reasons this behavior has been banned since 2014.