They don't need to be so Machiavellian. This forum is filled with Google and Facebook engineers. Some of them sincerely don't see anything bad in their companies. Others probably want to protect their stock options.
I am always amazed that being negative about Amazon is stomped out quickly in general. Just my experience where I wonder if this is by a team or they just have a lot fans.
I don't think we need to be that charitable. Seems well in line with the Amazon ethos to proactively control the narrative around them in online discussions.