This is propaganda level whataboutism that is attempting to conflate two different things.
1. The Obama for America campaign directly asked users permission to access their friend graph, which was allowed and stated in the permissions at the time before FB reduced app permission scope.
2. The action taken on that data was to cross reference publicly available voter registration lists to suggest those most likely to respond to an invitation to join the campaign sent by the first user. No consent was missed here either.
Whereas Cambridge Analytica:
1. Bought the data from a third party, who had slurped it down under the pretenses of "academic research" in a random quiz app. Already a couple layers of misdirection here. This was after FB had tightened up their data usage policy
2. Peddled the data for targeted harassment and voter manipulation with false or misleading info. The leadership pitched services such as staging blackmail by spreading rumors about an opponents sexuality, targeting them with prostitutes and then disseminating that info.
https://www.thedailybeast.com/ex-trump-consultant-and-cambri...
https://www.snopes.com/fact-check/obama-campaign-use-tactics...