… - well, I guess that depends on what you want to achieve. In analog times, film grain was mostly an annoyance people tried to avoid. There is a reason a 70mm film has a different visual impact than the S8-copy. Over time, people got adjusted to the grainy film look and film makers started to utilize the film grain as an additional dimension of story telling. Your reference “WORMWOOD” on Netflix is a prime example - by using the old film stock, even showing the sprocket holes, the film maker marks these sequences as “old” to the viewer. So in this case, grain is clearly used as a means of story-telling. But that is not always the case.
In the digital age, grain as well as camera noise tends to massively increase the bandwidth requirements for storage, transmission and processing. Depending on your goal, that might be of no concern. Certainly, if you are going for archival storage (and that is probably the case for the Kinograph-project), you might want to scan at the highest resolution possible. However, most of your budget, specifically your time budget, scales approximately with the square of your scan resolution. GPU-processing won’t really save your day here.
Actually, basically everything scales with your scan resolution: the price of your camera, which lens you need to use, the rigidity of your machine, how good you have to register the frames, the time you will need for processing etc. A single pixel of a 4k frame represents - over the width of 5.69 mm of a S8 frame - a dimension of about 1.4 microns on the film surface. That is a very tiny, quite demanding dimension in terms of mechanics and optics.
Coming back to archival storage: besides scan resolution another important thing often overlooked is the dynamic range of film stock. Not many digital cameras can cope with the dynamic range of color-reversal film, even in raw mode (scanning a negative is a different story). To capture all the detail (for example the increased grain in dark areas) you need to capture several different exposures and combine them appropriately. Until HDR-displays become widely available and HDR-formats standardized, you are probably going to store just the raw captures for the time being for later processing. By the way, if you are opting for HDR-scanning with consecutive scan passes, you are going to have some difficulty in aligning different exposure runs of high-resolution images precisely, possibly introducing artifacts along the way.
Coming back to another use case, in a way opposite to the archival case: digital distribution of private movie material. Here, you might even want to reduce the grain scanned by your system. Usually, this dramatically reduces the file size you are going to distribute. And it seems to be less annoying for some people to watch such material.
In addition, non-professional S8-material usually is also very unsteady/shaky. If you compensate this as well, again the file size of your material will decrease while casual viewers will enjoy the material more. Of course, you are deviating a lot from the original material, but it is often irrelevant to your viewers, which enjoy simply the old stuff shown in the material.
In summary, I think it will depend on the specific use-case how one is going to scan old film material.