I am no expert but I believe 1080 is here for quite a while yet.
If you are shooting movies for the cinema then yes you may need 4,5,6k but even TV stuff at the moment is still pretty crap as its compressed.
Here in the UK you actually have to pay extra for HD channels, all the normal stuff that is apparently HD is not even progressive, its interlaced.
4k is great if you want to recompose a shot and zoom in for 1080 and not lose quality, but other than that there is much more they can do with HD to make it better first.
There is too much of a bottleneck at the moment, and unless you own your own super computer and have LOTS of storage, the likes of us who aren't shooting big screen movies have no need at all for 4K
Let the camera manufacturers give us better DR and colour space first.
One of the reason why I like Black Magic even though they dont stick to their shipping dates, is they are trying something different that all the others have failed to do.
Our cameras could be (and are) much better than they are now, but the manufacturers see profits before better images.
Look at what magic lantern has done with the Canon, now you imagine what Canon "could" give us if they didn't have to pay their share holders.
I love to read all the latest pixel peeping stuff and get to grips with it, but tbh 99% of the general public couldn't tell the difference between a film shot with an iphone or an alexa if you didn't point it out to them.
HD will be here for quite a while yet, its not to say people wont be watching their 4k TVs very soon, but tbh most of the stuff they watch wont be in 4K anyhow, so its a feel good factor the same way TV with HD has been for the past 5 years.
FWIW I actually liked the hobbit in 3D 48fps as its the only 3d film that didn't make me squint or give me a headache
Motion blur is what people have been used to now for decades, and if everything was shot in higher frame rate then they would consider it the norm as their brain would get used to it.