It's important to keep in mind that many (if not most) people ad-blocking google ads do so because of the fear of malware (usually from youtube).

So to Google, killing accounts of malicious actors is a primary concern, and obviously you can wield a lot of damage to people through google's services if unchecked. And even with checks, every bad actor wears the mask of innocence when appealing.

So this puts Google in a rather intractable position. Without numbers it's hard to say whether they are leaning to hard towards stopping fraud (many false positives), or too hard towards giving accounts freedom (high levels of malware served).