These errors appear to come from one of the NVMe devices:
42:00.0 Non-Volatile memory controller [0108]: Samsung Electronics Co Ltd NVMe SSD Controller PM9A1/PM9A3/980PRO [144d:a80a]
Subsystem: Samsung Electronics Co Ltd NVMe SSD Controller PM9A1/PM9A3/980PRO [144d:a801]
Kernel driver in use: nvme
Kernel modules: nvme
If there's a different slot you can use try, if not you should be able to suppress the errors, to at least stop filling the log up.
As for the parity check it's using a lot of CPU, parity check is single threaded, and it's showing 100% CPU, which would mean it's being limited by that, but it doesn't make much sense with the CPU you have... Did you notice slower performance with anything else?