Actually here the problem may be a different one… because we do not only trigger the DISABLE signal on the M.2 socket, which would have to rely on the card honoring it, we also cut power to the card when the kill switch is flipped. So when you turn it back on the card has to reenumerate on the PCIe bus. We have enabled PCIe hotplug support for the port in Coreboot/Pureboot but not all cards work properly in this regard (likely a case not many manufacturers test for).
That being said, we have pretty successfully tested Intel AX200 and AX210 by now - of course also requiring a firmware blob. AX210 require a quite recent kernel to work properly (IIRC 5.16 or 5.17 and newer).
Cheers
nicole