LLMs can't even distinguish properly between a fruit with green flesh and red skin vs. green skin and red flesh, and you expect them to distinguish between ads and content?
Read the article, the ads are part of Google programmes/partnerships with advertisers and are meant to present buyable products that are supposedly relevant to the user's query.
I read the article. My point is that the ads won't be just the ones that the article describes, and clearly separated from the content; eventually they'll become part of the content.