Hasty Googling gives a bitrate of 85 Mbps for 8k video streaming with HEVC. Presumably if a physical media comes out, it would be closer to 400 Mbps if it was a similar compression ratio as 4k. I'm not sure what the bitrate of volumetric data would be, but I would guess less than or equal to the video stream.
So your gigabit connection would be getting close to saturation if you can find someone to stream you 8k volumetric video at the same bitrate as physical-disk media. At streaming rates, you'd be nowhere near saturating a gigabit link.
Human touch is extremely sensitive. I imagine that for sufficiently complex objects, bandwidth requirements may be onerous if aiming for the touch equivalent of 8k Dell Ultrasharp visual fidelity.
So your gigabit connection would be getting close to saturation if you can find someone to stream you 8k volumetric video at the same bitrate as physical-disk media. At streaming rates, you'd be nowhere near saturating a gigabit link.