Saying that ads make things worse isn't an interesting observation. That's just the internet. It's nothing specific to search.
Obviously putting ads in search is going to worsen the overall quality of search+ads. But that's not an interesting observation to make because we all know that already. It's by definition. And it's clear Amazon is doing that to make money from the ads, again not as a "Gruen transfer" effect.
>[It isn't "Gruen transfer" because it's an ad to make money.]
Seems more like clicking on ads is the end and Gruen transfer (via intentionally confusing ads with search results) is the means.
FTA: "The 'Transfer' part is the moment that you, as a consumer surrounded by a deliberately confusing layout, lose track of your original intentions." This still seems perfectly applicable to me?
FTA: "The last time I checked Facebook, maybe 10% of my feed was updates from friends. The rest was a combination of ads, memes, and influencer marketing videos..." So putting ads in lists where they don't belong is explicitly included in the definition, despite your attempt to exclude it.
Does it? It seems to return things with my search terms just fine. What is usually the case is that there are lots of items with some of those search terms that are also popular.
I see no evidence that Amazon is trying to make its regular search worse.
With sponsored listings there's a separate issue if sellers are bidding on keywords, but that's also to be expected.
It makes sense for Amazon to show other products on product pages and in checkout (as it does). But doing it intentionally during search would seem counterproductive. The reality is just that search is hard, and people are often bad at entering search terms.