The problem is, every thing gets upgraded and replaced almost annually. Not sure there will be a lot of difference. I do not notice much difference between my 2 difference models of apple tv's. I have had every generation so far. While cloud storage has replaced the need for TB HDD's, most people do not have 4kTV in every room of the house.
Our problem is with NowTV not living up to the premium price the subscription costs compared to the substandard AppleTV app. If I relied sorely on the AppleTV app and not the inbuilt one on my 4kTV, I would not be using NowTV.
The AppleTV box is a favourite of mine. I have a lot of Apple kit and am one of those who are more likely to upgrade 'just because' theres a newer shinier model.
However that said, I am intrigued with what a new AppleTV box can bring. Yes, the current hardware, even the 4K model is a few years old now without any updates - but as someone who does not use it as a games console and play games on it... I just use it for streaming services - I don't see what an upgraded chip will do for the TV watching experience.
I still find my 4K appleTV to be lightning fast and the best streaming box experience I have encountered. When I have to go back to the NowTV box to watch NowTV content in 1080p and 5.1 with the boost add-on.. I pull my hair out each and every time as its so slow, and clunky... and this is a Current Gen piece of hardware much newer than the several year old 4K AppleTV box I have.
Currently the only way to watch Sports on any supported NowTV device (including the Apple TV boxes) with a NowTV Sports Pass is live only.
NowTV doesn't currently offer on demand or catchup sports where you need to watch live or on a repeat broadcast.
There is also no red button service on NowTV for watching alternative live sports feeds, so you need to watch from one of the eleven Sky Sports channels transmitting at the time.