the RF noise form computer components is enough to be taken care of by regular metallic shielding, because the amps are low for actual compute operations. an inch of space on its own is an effective barrier. this is very different than having a wire running enough amps to power a space heater, located next to your data transmission lines. even having the GPU in its own external enclosure, you would not want the data cable to be bundled with the power cable for anything that pulls over half a kilowatt.