Rather than create a new thread, I'll reply to this one since we are having the same issue but in Word.
The problem is like described above. It started off with a one user last week but now has affected pretty much all but one of the devices in our division. We have special macros that are embedded into the QAT. We use the QAT as a tool for dozens of keyboard shortcuts but now the keyboard shortcuts are different because of the 4 default commands that we can't remove. If we go the "Customize the Quick Access Toolbar" page and try to remove them, nothing happens. The only way to get rid of them temporarily is click the little down arrow at the end of the QAT and uncheck them. But as soon as we open another document, they appear again.
I've narrowed this down to the word.customui I believe. The file does not exist in C:\Users\Username\AppData\Local\Microsoft\Office like it should. When I manually create this file and place in that location and try to update the QAT, the Word.officeui file is deleted. If I copy the customized Word.officeui file from the last device that still works and place it in the folder, all customization settings are ignored.
All devices running windows 11 and Microsoft Word for Microsoft MSO (Version 2311 Build 16.0.17029.20068) 32-bit