Kind of, yeah? A few years later I deleted my Amazon account because Amazon became the new AliExpress and I could usually find everything for cheaper on eBay.
Which is not an answer to the question “Was The Washington Post the tipping point where Amazon started to collapse?”, which you were responding to.
I don’t eat at McDonalds, but that doesn’t make me think they’re going to collapse. In fact they’re likely successful for precisely for the reasons I don’t eat there.