Seiki, Westinghouse and Element is not a big threat for Android TV when it comes to Smart TV OS. If a OEM uses non-Google approved fork version of Android then Google has the power to suspend their GMS license so most big brand will not use Fire TV.
Those brands don't excite me... I see myself buying a good TV, perhaps with Android TV as the OS, and then buying a Fire TV, that way I could have both FireTV and Android TV, since they don't always have the same Apps... Win-win
Amazon's consumer technology division's slogan: "me too!"
Competition is a good thing.
Remove that clunky ass interface and you might have a chance, Amazon.
The #1 reason I tossed out my 1st Gen Fire TV box was because the interface had all this stuff going on and my parents just needed to get to Netflix and Plex. There was no way for me to customize or disable parts of their home screen like there was on Android TV.
So, I tossed it out and got an Android TV device.
Remember when Amazon decided to enter the phone arena?