Amazon branded items don't bother me much, personally. I've found they're always reasonable quality at good prices. I've had an amazon backpack that I used for years before the pandemic, an Amazon mouse that I've been using for years, and so on.

No, what really irks me about Amazon is when I search for something and find a thousand products of different brands that are essentially the same, none of which are what I'm looking for. Usually this happens when you want something really specific.

One example, I was looking for a moss pole to train my tropical houseplants on. A requirement for me is a pole with real moss: coco coir doesn't hold enough moisture to build aerial roots on a tropical plant. I search "moss pole" on amazon and for pages and pages I only see coco coir poles of the exact same design (I tried this again right now and I see there's exactly one pole with real moss on the first page, an improvement for now)

This phenomenon has happened to me multiple times, where my search results in dozens of brands of seemingly identical products that aren't in the least what I want. Combined the usual quality problems of these nameless brands, it gets very difficult to buy anything on Amazon unless I already know the exact brand to buy from.