Anazon is better than ever for brand name, known buys. Eg I recently ordered a UHD bluray movie, took about 15 seconds end to end and arrived in a day. They are terrible for everything else. Eg I bought a reading light. Which was a 10 minute sorting excersise trying to figure out which of a dozen nearly identical products was the least likely to burn down my house. Then trying to uncover which had real reviews and no…
In theory, with the right tools competition could sort that out.
But this theory doesn't work, not in Amazon, and not in many other online marketplaces.
So the solution is: exclusive brands, controlled by Amazon.
Amazon works hard on scaling that strategy.
And once Amazon is deeply invested in that strategy, a low-quality marketplace seems like a good thing.