What's more, I suspect that if this exact same thing had been done by a company working for Obama's or Hillary's campaigns, nobody would have batted an eyelash.
PS - the reason that the regs wont happen during the trump years has nothing to do with the collusion investigation. He's put a mandate in place that for every reg to go into the federal register, two have to come out. His administration is in general very anti-regulation. Therefore, yes, absolutely no way he would ever regulate it ... but not for the reason you hypothesized.
Quite literally his campaign invented the tactic of scraping your friends list as a way to persuade voters. The important difference was CA used data that was gathered under the misleading guise of a personality quiz.
Cambridge Analytica had 200 clients. Now not all of those are major elections but CA is also not the only player who's been doing this. Governments and shady organizations have been perfecting media-based mass manipulation for decades/centuries.
While I agree that I think the Obama campaign has largely gotten a pass for similar data collection and voter profiling activities, I think that part of the reason its getting such attention now is some of the accompanying scandalous tactics of CA being revealed along with their data efforts. Some of the undercover videos being released, particularly the one regarding the Sri Lankan election, look pretty bad.
The big difference is that the Obama campaign didn't try to hide their intention of having you sign up with Facebook. The 'research' firm tricked people into thinking it was a research study when they were in fact harvesting data for different means.
PS - the reason that the regs wont happen during the trump years has nothing to do with the collusion investigation. He's put a mandate in place that for every reg to go into the federal register, two have to come out. His administration is in general very anti-regulation. Therefore, yes, absolutely no way he would ever regulate it ... but not for the reason you hypothesized.