Even (high-end) consumer SSDs can saturate a PCIe gen 4 x4 link if you are doing sequential reads. Non-sequential hurts on even enterprise SSDs.

Not in the context the person you responded to meant it. Yes, you can very easily get 50GB/s from a few NVMe devices on a single box. Getting 50GB/s on a POSIX-ish filesystem exported to 1000 servers is very possible and common, but orders of magnitude more complicated. 500GB/s is tougher still. 5TB/s is real tough, but real fun.