Wonder how that'll work with the library of apps that support Fire TV today.
Will they run in an android compatible runtime?
Will they need to be recompiled for a new OS?
Sounds like they want to try what BlackBerry did back in 2013 with the release of BlackBerry 10. A new OS that developers can write for, or just port the existing Android app and run in the Android runtime built into BB10. It worked, but was not well optimized. BB10 eventually died 8 years later.
(Technically, the OS still runs on the phone, but all back-end ID/Protect/support services and app store are all shut down).
Now, Amazon does have more resources and maybe slightly more pull (BlackBerry had to beg and even offered money to developers), and certainly more market presence, but they seem to be proposing a true third ecosystem.
I just don't see that working out very well.