Calling this "hijacking the Amazon app" is hyperbolic in my opinion. They replaced the shortcut in the app drawer. To me this looks like normal scummy OEM behaviour, like pre-installing spyware, "anti-" malware, adware etc. which sadly pretty much every mobile/computer manufacturer does.

Replacing the OS is one of the first things I do with every laptop, PC and mobile device to get rid of (most) crap that was installed without my consent.