4k video is OFF by default.
There goes your main argument that mainstream users will run out of space because of 4k video.
That is not my main argument. I have stated several others you keep ignoring:
- Photos and videos are now larger (12MP and 5MP upgrade, ignoring 4k)
- Live photos are twice as large
- App size can now be 4GB. Really one or two new graphics intensive games to use that beast of a CPU and RAM, that is all you get.
- More apps are giving offline storage options (ie Amazon video) for streaming