This is hardly something that is marketable.
The set-top boxes like Amazon's Fire TV aren't gaming centered devices, they just add some gaming features to a device that was designed to either bring smart TV functionality or stream TV Shows and Movies digitally through the internet, so it's fine for them to be that weak.
I doubt Nintendo would want to be one among many of those kinds of devices and get lost in the crowd of an even busier space than the dedicated console market.
Nintendo would be better off becoming a 3rd party publisher than doing the set-top box, tablet with some gaming functionality type of thing.
For Nintendo they're making a dedicated gaming platform with NX, so the core features need to be gaming focused, not an afterthought.
Most likely NX is at it's core an OS that can run Nintendo's future games on a multitude of devices Nintendo wants to release them on. Iwata's own comments likening NX to how Apple and Android Apps can run on multiple types of devices eludes to this likely being the case.
We haven't had any rumors pointing to NX being a marginal step up from Wii U in performance or sitting around that level of power, we have however had comments from fairly reliable sources like Emily Rogers or Nerdleaks hinting at it being pretty good compared to PS4 or beyond that,.
We've even had leaks stating that it's 2X PS4, around PS4K and potentially features some kind of supplementary cloud processing system (this was shown in Nintendo's own filed patents).
There's also been a patent showing a handheld, with tech closest to XB1 in performance that can stream gameplay to your TV through a HDMI dongle (that kind of a thing would negate the need for a Vita TV style box).
It's possible that Nintendo are just going to market NX as an OS, that they can run on a bunch of different devices and that's why we're not hearing about a single console or one specific set of specs.
The fact that sites like Wall Street Journal said Nintendo were sending out "software dev kits" could indicate that NX is meant to be a flexible product that isn't limited to one form factor of device.
Now the whole supplementary cloud computing thing could mean that if you own more than one NX device, they can share the processing load and being in close proximity, using something like a Wifi-Direct they can talk to each other with significantly lower latency than having to access servers miles to hundreds of miles away (which is a big issue with cloud processing like Azure or PS Now).
That could easily boost the processing capabilities available to each user, since some people do like to buy more than one unit and if Handheld and consoles could work together to run a game then that would make for a better experience for the end user(s).
This could mean if you buy a tablet it doesn't leech power from the main console, but rather it handles what it needs to from the core game and the overall experience is better if more than one person is playing local multiplayer.
When gaming is your core focus it makes no sense to release a new platform that is barely any more powerful than the current failed one, especially when you can't possibly have a feature that can make it blow up in sales like Wii did.
An OS style approach puts the games at the forefront, it makes your platform flexible and the possibility of locally sharing processing load in a pier to pier cloud network potentially makes for a very powerful, evolving product that could be very attractive to gamers.
Vita and Vita TV didn't sell well, in the same way that Wii U didn't sell well, why would combining that kind of a thing make for a highly marketable and beast of a sales opportunity for Nintendo?
Also your reasoning behind Nintendo going with Arm doesn't make much sense either, X86 CPUs can be very low on energy demand now, especially with the advent of 14nm Zen tech from AMD or Intel's own processing tech.
Polaris is also very low on power consumption.
I don't think we've had a single reliable source hinting at what the OP suggests, it just doesn't really make a lot of sense to be true, much like the idea that NX is a PS Now style game streaming service.
It's not really attractive to a big audience, latency prevents it from working well, reliability of broadband isn't there to really make sense as this being the main feature of the system.
The core idea in this thread doesn't make sense at all, sorry OP.
