Lol, you shouldn't just dismiss the guy because his answer isn't quite there. An EMD will most certainly help, but links obviously are important too...
And look - EDITED TO REMOVE THE ACTUAL URL he is ranking #1 US and UK lol.
I'm showing that one ranking 3-4 (3 for singular "speaker" 4 for plural "speakers"), I didn't really look at the competition, but guess what is ranking in the 2-3 slots ahead of that site? Amazon pages, just like the OP was asking about (well, except they are product pages I'm seeing not category pages)...
That said, in my experience the difficulty of beating Amazon category (or product for that matter) pages can vary pretty wildly and you need to do more research.
There are cases where it is ranking purely because it's Amazon, it's not really optimized at all of that search, doesn't have much internal link juice and no external links pointing to it but no one else has targeted the keyword so Google said, "Hey we like Amazon, let's put one of their pages on here."
But there are other times where the people in that niche have actually decided Amazon is a good place to buy the product so whenever they talk about it in blogs and forums they link to the category page or to the specific product they bought or they post to ask a question about a product they're looking at and link to it. The more of those links there are, the more solidified they're going to be (honestly this applies to any website though, Amazon just has enough authority to get in there without links sometimes and that solidifies them even more once they do get links).
A couple points to keep in mind:
Amazon's category pages tend to have significantly more internal link juice directed at them than the individual product pages. (which again is why they end up ranking when there's no one else targeting the word)
But the category pages tend to have next to no actual content.
The product pages, if put together well (which many/most aren't tbh), contain significantly more content (bullet points, descriptions, reviews, Q&Q, etc) to help make it relevant to the keywords, but typically will have less internal link juice (let's face it, how many pages of Amazon's website do you think point to that OXO butter dish I bought a while back vs how many point back to the "butter dish" category or whatever subcategory of kitchen stuff butter dishes are in?)
