Suppose an R5X with a 60MP sensor has the option to record, internally, oversampled 8K as ProRES RAW or regular ProRES, would that fit your use case?
The allure of RAW is not having debayered the image allows for "moderate" file sizes.
A bit of math:
DCI 8K@12bit@24fps uncompressed RAW uses 72900 MB/min ≈ 71 GB/min (8192*4320*12*24/8/1024^2*60).
The R5's implementation applies some compression (only intra-frame) cutting the bitrate into about a fourth (18668 MB/min ≈ 18 GB/min).
Now when you debayer the image, you'll generate 3 times more data because now you have 12bit for every color channel for every pixel. (uncompressed: 218700 MB/min ≈ 214 GB/min) You somehow need to compress that extra information to get back down to RAW level-bitrates. You can do that with inter-frame-compression which is very heavy on your PC during editing, especially on 8K and especially at these bitrates or you need to apply more lossy compression. Both of which you don't want and more data is also hardly justifiable (that's then less than 56min/TB which the "normal" RAW on the R5 uses! ouch!)
So no matter what container you use, oversampling needs debayering, which just increases the amount of data. That's why for me RAW is the way to go. So I would try to avoid oversampled 8K.
As for the rumoured 60 MP applying a similar amount of compression as the R5 reduces the amount of time per TB by about 25% (~14min) and for me that doesn't make sense. And referring to what EOS 4 Life said: you can easily apply a bit of upscaling which only costs some time during the renders (you may sleep during the export anyway...) and not 30% more storage for EVERY file.
We're also always talking about what goes into the NLE, the output is always heavily compressed as you cannot see the difference during normal inspection, but the amount of artefacts you see when pushing the image is greatly minimised if you input the highest quality possible.
Exactly 8K makes 8K delivery more difficult for me.
may I ask where do you need to deliver in 8K? Normally, when you have gimballed footage you'd might only need a 1-2% crop for stabilisation at most, which you can easily upscale back to 8K without any visible problems.