AdSense is the one that people underestimate. It's a piranha pool of liquid cash, billions-scale impressions and near global outreach. Any sane nation would have banned it decades ago, unless it was propping up a global influence campaign for their government.
I am deeply saddened that it was developed by the hero of modern rendering, Eric Veach.
I am more concern with how they make scam much less detectable.
You can hyper-target your ad or scam to vulnerable individual.
Unlike traditional media, like newspaper, you can post an ad with no visibility outside your target group -- which is hard to discover.
The report button is just some generic "second look" and automation within the same organization, there are no oversight.