There are enough legitimate advertisers willing to buy ad space in Apple News to generate ~70% of the profit Apple expects.

Scams, you see, make more profit per customer, and thus can afford to spend more on ads per customer. This creates an upward pressure on ad prices, on top of the extra ads sold.

This is why abuse prevention at major ad platforms is so consistently lackluster. They want to stop some scams, the most obvious and and the most illegal kind, so that they can say they tried - including to regulators, and to major companies that also buy ads from them and don't want their ads next to penis enlargement pills. But actually stopping all fraud and scams could cut into their profits in a meaningful way. So there's no hurry to build better ad quality control systems, not at all. Actively staying on top of ad fraud is paying more money to make less money.

Facebook is a major example of this kind of dynamic in action. They actually had internal estimates of how much it would cut their revenue to get rid of the majority of fraud, and were silly enough to put them in the writing.