In the title, I wrote "at a time" because if I refresh desktop (pressing F5) one of the only two icons is replaced by one another. It seems refreshing "shifts" the display icons with the ones that come immediately after.
I tried these solutions:
https://answers.microsoft.com/en-us/windows/forum/all/overlapping-icons-on-windows-11-desktop/c84fa32f-beb7-437c-8460-26e28302f9f6
https://www.makeuseof.com/windows-11-missing-desktop-icons/
https://blogs.eyonic.com/why-all-your-desktop-icons-suddenly-disappeared-on-windows-11/
https://www.howtogeek.com/805889/how-to-restore-missing-desktop-icons-on-windows-11/
I tried all the methods exposed, but none worked.
I also tried the command sfc /scannow, followed by a restart of the PC but nohing worked.
The most strange fact is that the desktop is sync to OneDrive. In the "Desktop" folder of OneDrive (accessed to the File Explorer) I see all the desktop icons that in theory have to be shown in the desktop.