4K is certainly enough for now. The poll earlier this year showed that only a small percentage of people here even shoot 4K. If you want something that high, get a real video camera like the C series.
Care to share why we need 8K over 4K now?
The main reason why I don't contribute in this kind of forum any longer is because people are here with an attitude to fight one another. If that who you are then please do not read my comment, but if you genuinely want to know why I would value very much a 8K camera then here it is. It is my opinion and my own need, it could make sense or not to you.
When a camera moves it invites the viewer to put himself in the shoes of the character. When it is equipped with a 35mm or so, on top of the movement, it helps you to see what the character sees, to hear what the character hears and if it goes for a close up it insists on you to feel what the character feels. The ability of the camera for you to sympathize and empathize with the subject is one of the most difficult tasks facing any visual storyteller.
A camera is only a tool, but it is the tool that helps a storyteller to accomplish his task. Camera movement, camera height, crop, sound, rack focus are examples of these tools that you need.
We both know that there is a big difference between a photography and a videography as a tool for storytelling. Slow motion is the biggest tool so far that tries to fill that gap. It allows the camera to tell the viewer "slow down a little bit and take a time to process more of what you see". In other word, it is yet another tool that a storyteller can use to engage the viewer even more.
I own and use a 1DXII. It can do 4K at 60fps, but I rarely use that. Whenever I use it, I know that I reach the physical limit of my camera. I know that I am stressing my gear and my head begins to worry more about my tool than worry about my craft. That is not a correct way to work.
Ability of a camera to shoot 8K30P tells me a benchmark of that camera. With such capability I won't hesitate to shoot 4K 60fps, and even 4K 120fps; which is the right frame rate for a successful slow-motion, as a tool that fills the gap between video and photography.
I hope you see the reason, why a 4K shooter like me begs for an 8K capable camera. With the need for 8K30p all other accessories will follow and catch up, and makes my need of 4K 120fps even more fulfilled.
Finally, if you shoot like everybody else, how could you stand out? We may not see the need for 8K today, but the day it comes to reality people will find a creative way to use it.
Dragging the technology to stay behind in the day of my grandpa, because it worked for him and his generation, you simply are killing the art of storytelling.
I used to be a photography only storyteller, but as I advanced I realized that there were too much to say and my tool was not able to help me out any longer.