"you can be sure that this is, for better or worse, the official company response"
Quite the opposite: there's absolutely nothing official about it. It isn't published on an amazon domain, doesn't carry any signature as amazon, and the only evidence that this is in any way related to amazon is that the guy works at amazon.
"there's absolutely nothing official about it"...except that it's coming from Amazon's Jay Carney, who is described as "Senior Vice President for Global Corporate Affairs at Amazon". Could his Medium site use a custom banner to show Amazon's letterhead? Sure (I don't know, I haven't logged into Medium in awhile to know its design/customization options). But this message is signed by him, acting in his role as Amazon PR. Quibbling over whether it should've shown on an Amazon domain vs. an outlet like Medium does nothing to change that.
Senior executives are usually careful to point out when they're not speaking for the company. Carney identifies himself as an SVP at Amazon, uses "us" and "we" throughout the piece, and refers to internal records and emails he would have no reason to access otherwise.
