Sounds like theoretical mumbo jumbo really. In the real world I'd wager there's not going to be much difference, if any, between the two in that regard. PCIE 4.0 level SSD speeds are a pretty significant expense over 3.0. I can't help but think that particular investment is misplaced.
AMD Ryzen 7 5800X | Fractal Design Celsius S24 AIO | Gigabyte X570 Aorus Elite | 2 x 16GB G.SKILL Ripjaws V DDR4-3200 (14-14-14-34) B-Die | MSI 3080 VENTUS 3X OC 10G | Creative Sound Blaster Z | Samsung 970 EVO 500GB M.2 NVMe SSD | WD Black SN750 1TB M.2 NVMe SSD | Samusng 850 Evo 500GB SSD | Seagate Barracuda 2TB | WD 640GB Black | Asus BW-12B1ST 12X Blu-ray Burner | Fractal Design Define R5 case | EVGA SuperNOVA 750 G2 PSU | Win 10 Pro | 1920x1080 w/ 48" LCD TV
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