Yep, looks like some form of protection, see if it's this:
https://forums.unraid.net/topic/110835-solved-help-with-a-sas-drive/?do=findComment&comment=1011689
Disk started generation errors as soon as it was connected, SMART looks OK, but you can run an extended test (on the CLI since the GUI tests won't work with SAS devices) and/or make sure it's not formatted with protection, this usually appears on the SMART report when enable but not always.
Looks like the stats don't work during parity copy, it's showing reads and writes for disks 1 and 3, and they are frozen since they are the same as the previous diags.
Most likely suspect here would be the original parity disk, could be reading slow, you can test with the diskspeed docker after this is done or after canceling the current copy.
Xorg is using 100% CPU, not sure what this is about, try booting in non GUI mode to see if it still happens.
P.S. pre-sales forum is for ordering, product question, etc, this should have been posted in the general support forum.
Array is stopped during the copy, can you post new diags just to check the array stats? The ones from before are weird, though I never checked before during that, they might no work correctly.
You can do that, though it's possible some data fails to copy/move, but at least you'll know which data is affected, another option is to use ddrescue to recover as much as possible.
Looks like it does.
It's possible, but parity won't be 100% valid, so if you then replace the disk the rebuilt disk will have some data corruption, unless the read errors are in empty disk space.
I didn't mentioned it but obviously the low end 980 should still work, could be some compatibility issue, should be OK with a different model device but make sure it can be returned if it isn't.
Apr 5 07:47:21 Server kernel: nvme nvme0: I/O 13 QID 0 timeout, disable controller
Apr 5 07:47:21 Server kernel: nvme nvme0: Device shutdown incomplete; abort shutdown
Apr 5 07:47:21 Server kernel: nvme nvme0: failed to set host mem (err -4, flags 0x1).
Apr 5 07:47:21 Server kernel: nvme nvme0: Removing after probe failure status: -4
Apr 5 07:47:21 Server kernel: nvme nvme0: failed to set APST feature (-19)
NVMe device failed to initialize, try it in a different PCIe slot if available, or with a different device.
Problem with the onboard SATA controller, quite common with some Ryzen boards, look for a BIOS update or use an add-on controller (or a different board).
I would guess the stopped refers to the array in this situation, but seems to be going very slow, log is spammed full of USB disconnects, but not seeing anything else.