When I forget to sign in to YouTube, I see the same pattern, shitty ads that are clearly only allowed because otherwise YouTube wouldn't have sufficient ad inventory to meet their internal KPIs.
The reality is, of course, that Google and its ilk doesn't give a single rat's ass about people falling from scams or getting infected by malware. Scams and malware pays better than "ethical" ads (to the degree that such a thing exists). It's a travesty that there are apparently no laws against their behavior.
In the USA I’m pretty sure advertising scams - even the more ‘benign’ ones like claiming a product does something it doesn’t do or lying about its efficiency - are illegal. There’s just no - or not nearly enough - enforcement.
The situation’s been like this for a few years now.
If she had had more time, I could see Khan going after fake ads as well. There's nothing to me that suggests that she was deliberately ignoring fraudulent ads when she was extremely pro-consumer in nearly every other policy.