As someone who left Microsoft for Amazon, most of the things I hear about Amazon align much more closely with my experiences at Microsoft. We're talking about companies that employ thousands of people, you're going to hear different stories from different parts of the company.
It's entirely possible for a "publicity bubble" to cause all this. A big article got published ripping Amazon, got a lot of shares and views. For a while after that, anything negative about Amazon that seems authentic gets upvoted hard because it's what people want to read, and it lets them feel what they would call justified rage. People like that and people who just want forum karma and attention aggressively seek out or sometimes even make up stories to meet what these upvoters want to read. Stories that buck the narrative get downvoted and ignored. And just like that, you form a big popular impression of something that may be false or grossly exaggerated.
I don't know that the impression is actually false in this particular case, but these things can happen, and you'd be wise to not take the "internet consensus" too seriously.
The closest sibling to the grandparent of your comment, just -four-or-five- [Edit -- went back and counted:] seven comments higher in the thread, explicitly refutes your "publicity bubble" thesis.
My impression has been that Amazon is highly variable internally, a bit like MS (which I actually do read horror stories about).