You can't compare a 5.x' 4k display with a 4k photo/video and they don't need to be related.
I'm sick of the spec war and the overpriced stuff which comes with it but it needs to happen sometimes, i guess.
Why are you sick of the spec war? Our phones and all components are improving at a huge rate.
Improvement = good the majority of time.
Most times its the implementation of the improvement that makes it suffer.
I for one think a 4k Display on a smart phone is ssilly because I already can't see pixels on qhd phones, the performance will probably be downgraded because the processor will use more power, and battery life will suffer most likely.
However in 2 years time most of these downsides will have probably been weeded out.
Like all iPhone fans probably said a few years ago when most android phones a few years ago about HD screens, the same applies here.
Apple is falling behind in many ways in terms of hardware now, they certainly don't have the best screens, there are better cameras, better speakers, better performance and faster phones etc
Where as in the past (iPhone 4?) I would say apple clearly has the best screen, best camera, chip was amazing etc
Apple is being very slow at evolving the iphone compared to its competitors.
Of course they do offer a great ecosystem that ties in all there hard ware ( phones, tablets, computers etc)
However now days you can basically do everything that Apple do with an app. Push bullet basically allows you to control your phone on your computer to send apps etc
Google photos can sync all your photos to every device etc
Google Drive is better than Icloud in many ways and is universal.
So in many ways it's ecosystem has been caught up already.