Because your mega advertisers (Coca Cola, Disney, et al) are being played next to scam ads.

Also I think this should be a two way street. If content creators need to moderate their content lest they be slapped to death by Youtube to help the advertisers, advertisers also have a responsibility to ensure their advertisements do not cause issue for content creators and/or viewers.

It's unclear who currently runs Youtube, but they have been making bad decision after bad decision. Youtube is now extremely hostile which goes against the values it once held when it first grew.

Because it makes you an accomplice in a crime? I mean, it's not like these things slipped through the system: you were alerted to them, you took an action, you claim you reviewed them, and that you are fine with them. That is basically a statement that you are fine with being complicit in a scam.

* Risk of popular support for ad-blocking, because of all the scams.

* Risk of regulators taking an interest, because it shows the ad industry can't self-regulate.

* Risk of regulators taking an interest, because their voters are getting scammed.

* Risk of regulators taking an interest, because celebrities complain.

* Risk of regulators taking an interest, because deepfakes.

Reputable companies generally don't want to advertise in an environment that could be damaging to their brands. This is why Google/YouTube created the "advertiser-friendly content guidelines". For the same reason a number of big brands pulled their X.com/Twitter ad campaigns.

Ad companies usually don't own the broadcast network too.

Garbage ads damage a brand. Google doesn't do anything because they think Youtube's goodwill will last forever. It won't. They've already ratcheted up the ads to a level where regular users are complaining.

Would seem to me that scammy adds negatively impact the reputation of your product. Makes it easier for a competitor to gain traction "I rather use Y, much safer and more reliable than YouTube".