See it though the lens of 2005 not 2024. Design standards where different, the reaction of users to banner ads or spam was not the same, SEO was still nascent industry, websites designed to game the engine was very small issue if it existed at all, every website looked like that at the point in time.

Here is how Yahoo still very much juggernaut in 2005 looked https://www.webdesignmuseum.org/gallery/yahoo-2005 for context.

No it absolutely doesn't "scream spam" at all. You're just seeing it through 2020s eyes where you assume any site claiming to do price comparisons of broad categories of product couldn't possibly be accurate, impartial, human-curated/checked, not be gamed, swayed by fake/paid reviews, compensated under-the-table or biased by affiliate commissions etc.

You're forgetting very quickly that back in 2006, ~88% of search results were organic and only 12% paid. Things have changed quite quickly.

But it wasn’t, which hints that detection models should be adjusted. It’s a judgement in the same category as “he looks criminal”.