In theory, Amazon's T&C's attempt to pass on the risk of loss to me after delivery of the item to a carrier. In practice, this is far less clear, because of merchant agreements / cardholder agreements and overall FTC regulation of goods sold directly to consumers.
But it may be moot, anyways: if Amazon decides to screw me, they have a bunch of digital assets that they hold hostage and will remove my access to if I initiate a legal dispute or chargeback, even if I'm in the right.
And I'm not just using the term "responsibility" im a moral sense here - consumer protection laws in many places agree with this. The seller is an "informed market actor, taking on the risks of the transaction". The consumer is not an "equal market actor" and is therefore afforded protections from the risk.