Consider for a moment that 4k resolution is not easy to obtain from film - you need to shoot the whole thing digitally to really get the right product.
I also don't much care for how 4k looks - or the bandwidth needed to transport it around.
I also don't much care for how 4k looks - or the bandwidth needed to transport it around.
Why's it not easy? You just do a 4k scan of the film don't you?
And again, resolution is just a small component of the final image quality. There is a major 3.2(ish)K camera on the market that has substantially better IQ than 4 and 6K alternatives. And another 6K camera that has substantially better IQ than 8K options.
As for upscaling, we're probably better off leaving that for the end user as better upscaling algos are created and deployed all the time and baking it in from the studio locks us into what will soon be old methodology.