You are correct the process is an Apple process and not a third party process, I just don't have it currently running on my computer either from an EtreCheck report showing high usage or when looking in Activity Monitor and searching for the process.
I have seen reports where others have that same process running in the 96-100% range, but there has not been anything found that would point to a cause. I also tried comparing your EtreCheck report, which is clean of the "junk" files normally seen, and there was nothing consistent across all of them.
- Most other users did have a Fusion Drive, but there were even some newer Macs that only had SSD drives.
- One other user had Pixelmator Pro, but most did not.
- It was seen not only on Sequoia, but also Tahoe. Did not see it on any earlier versions of the OS.
I asked about the use of the HP printer only from a post on the HP site about an error dialog showing a WKBackgroundShortcutRunner error dialog that appeared to be resolved by removing/updating the drivers. Of course the WK refers to the WorkflowKit where the process resides in the System folder, but that is not the case for you and no other causal link would lead me to believe the printer is the cause.
The one thing I am not sure about is if that process is the cause of the beach balling or if they are just 2 things happening at the same time. It still does not explain why some users are seeing high CPU use and others are not. I could only come up with a couple of other tests to investigate further:
- Add a new (Test) user and see if the same thing happens when logging into that user.
Add a user or group on Mac - Apple Support
- And of course the worst case scenario of a Factory Reset. You obviously would want a backup and start with the clean system to test, then add software and devices one at a time in an attempt to pinpoint. You would want to be able to use the backup to restore at any time. I don't have any reason to believe this is the answer and purely an attempt to try every option possible.