For me, Amazon used to be a bit like going to a mid-tier department store. Items were curated and higher-quality than, say, dollar store or clearance items and there was a certain level of trust with them as a retailer. I would buy something from a known brand and enjoy it, and rarely do a return. Customer service reps were a phone call away and I could google the model number and see other people's experiences with it as well.
Now I'm seeing so many sponsored results to brands I've never heard of and seemingly only exist for drop-shipping or rebranding some OEM product. Worse, the non-sponsored results would also be no name brands, where I'd gravitate towards the ones with high reviews. Then I buy the product and see a little gift card I could monetize if I was to review the product with 5 stars, so seemingly most of those reviews are fraudulent. Worse again, the quality on this product is below, sometimes even way below, a normal brand I could get retail locally but priced about the same. I must return 1/4 of the products I buy because of poor QC or later breakage from normal, if not, light use. Support or customer service for these brands is almost non-existent too and this brand will disappear in a year anyway, so why bother trying to build any sort of reputation. Amazon is always happy to do a return so it solves that problem, but its a still a big hassle and I'm sure the carbon footprint of all these returns is scary. Then I'm playing random OEM roulette again with a similar product that will also have fraud reviews and 5 star review coupons inside of it.
I also dislike the dark pattern format of the site, which shows sponosered results in very small text and puts it in between related items. I'm not sure what Amazon's Choice really is, but its almost never a product or brand that I would consider trustworthy and I imagine is just a product that is giving Amazon good margins. In a curated department store model, recommended items would be actually recommended by staff and taste-makers at the cost or benefit of the reputation of the store. If Macy's is recommending a Braun coffeemaker, then its probably going to be a good coffeemaker as Macy's wants to please me as a Macy's customer. If Amazon recommends one, its just going to be some in-house rebrand or random OEM brand with lots of suspicious reviews (tons of 5 stars but also tons of 1 stars, with not much in the middle) and with positive reviews being either "amazing i love it!!!" or referring to an entirely different product (bots?) and negative reviews being in competent English and verbose and detailed about all the things wrong with this product.
I think like with any capitalist endeavor, without proper oversight and regulation, it naturally falls into a race to the bottom and "low road" capitalist outcomes. Amazon has been left more or less alone by legislators and its, of course, gone as bad as it can and I imagine will only get worse over time. Amazon moving from the department store model to the random street bazaar model is good for the bottom line but every year it gets harder to shop there as no-name brands with no support and fake reviews dominate its marketplace.