During the 2016 US Election, undecided voters were targeted and bombarded with negative Clinton (much of which was false) and pro trump political ads. Studies s

During the 2016 US Election, undecided voters were targeted and bombarded with negative Clinton (much of which was false) and pro trump political ads. Studies show that this played a significant role in DJT's victory, and that Russia had a hand in it. If Facebook did not allow such deep personalized ad targeting then this strategy would not have been effective. Look into: Cambridge Analytica Scandal