I imagine they would be more like product placements in film and TV than banner ads. Just casually dropping a recommendation and link to Brand (TM) in a query. Like those Cerveza Cristal ads in star wars. They'll make it seem completely seamless to the original query.

I just hope that if it comes to that (and I have no doubt that it will), regulation will catch up and mandate any ad/product placement is labeled as such and not just slipped in with no disclosure whatsoever. But, given that we've never regulated influencer marketing which does the same thing, nor are TV placements explicitly called out as "sponsored" I have my doubts but one can hope.

Yup, and I wouldn't be willing to bet that any firewall between content and advertising would hold, long-term.

For example, the more product placement opportunities there are, the more products can be placed, so sooner or later that'll become an OKR to the "content side" of the business as well.