I bought the new Samsung 980 Pro 1TB (PCIe 4.0) and put in the Lenovo Yoga Slim 7 (PCIe 3.0), I saw only ~10% decrease in raw performance : r/AMDLaptops
MSI SPATIUM Series M.2 2280 1TB PCIe Gen3 x4, NVMe 1.3 3D NAND Internal Solid State Drive (SSD) M370 - Newegg.com