My take is that it's because there is still competition in Sweden to keep them on their toes. Once they have decimated the Swedish high street, like they have in the UK, they will start cutting costs.
I've had crappy service on UK high streets long before Amazon. A keyboard I got from Tottenham Court Road stopped working within a week so I took it back in person. The shop manager tried to tell me I had to send it to the manufacturer. He backed down when I put the phrase "contractual relationship" into a sentence.
It was one of the many independent shops on that street. Curiously, the place is lately like a physical version of how Doctorow describes Amazon search results in the article: the same narrow selection of products, repeated at different prices.
yeah, the UK high street was definitely ripe for the taking. And Amazon with its cheap prices, no-nonsense customer service and return policy was miles better. The point is that it's no longer really the case.
I'm sceptical of Amazon's ability to do this in a country with strong consumer protection laws. If Amazon becomes the default for every online purchase in Sweden, and then enshittify, assuming there aren't other options to fall back on, the pressure will be pretty heavy, while in the US, that pressure basically doesn't exist.