Industry insider sources inform that Intel's Comet Lake lineup of desktop CPUs will not provide support for the PCIe 4.0 standard as advertised back in late 2019. Intel's CPU shortages combined with the impossibility to adapt circuitry in time have led Intel to completely drop support for the PCIe 4.0 standard on this year's desktop platform.
https://www.notebookcheck.net/Intel-drops-PCIe-4-0-support-for-upcoming-Comet-Lake-desktop-CPUs-postpones-launch-to-April.451046.0.html