Looking online this seems to be quite a common problem. Usually after periods of inactivity. Despite not actually using the PC it shows 100% disk usage and of course stops.
I’ve had a similar issue, but I wasn’t able to work out the problem for myself. The problem PC is actually in with Novatech’s techs for the second time and in theory they’re taking a look
The link you pointed to refers to an issue related to system with PCIe based SSD storage using the AHCI rather than NVME Protocol. It could be related but if you could not find the registry key described then its more likely your issue is caused by something else.