[giantrobot]

Facebook and the Internet were a bit different in 2008 than they were in 2016. Facebook had fewer than 150m active users and they skewed young. The "news" feed was actually stuff your friends posted and using social media for a political campaign was novel.

Fast forward to 2016 where Facebook has two billion active users, a majority of whom use their location/behavior tracking app. They also have 12 years of user extremely detailed user graphs and own a significant percentage of online advertising (tracking). Their business model has also changed to specifically sell microtargeted ads. They've also resisted all types of regulation of political advertising.

There were misgivings about social media political advertising in 2008 but up to that point social media was just crowd sourcing of bullshit. Since 2008 it's become far less social and really just become a big advertising vector. Whatever misgivings anyone had about it would have vastly underestimated its impact.