Hi,
same problem for me (Windows 11 Pro) with 2 "link" to OneDrive directly in 1st level in Explorer.exe after Home/Computer (in French Bureau).
They appear like "<My name> : personal"
I've found in CLSID 2 keys related to OneDrive, one with "OneDrive : personal", and the other only "OneDrive".
But this tip didn't worked for me.
Even after rebooting for one of the 2 IDs, the value "1" reappear for the name "System.IsPinnedToNameSpaceTree"
Instead, I've found an other solution, still in Registry.
Go to HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace
I'd 2 "folders" (or keys) related to OneDrive (the same IDs I've found in official MS tip).
I've renamed the key related to the ID of "OneDrive : personal".
In my case :
\HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\Desktop\NameSpace\REMOVED_TO_AVOID_DUPLICATE_{018D5C66-4533-4307-9B53-224DE2ED1FE6}
No need to reboot (or killing explorer.exe), only closing all Explorer windows and launching a new one with WIN+E
EDIT (some hours later) : it's not fully OK, because I've seen that some times after renaming this entry, it's appear again in the registry (and I've twice again the OneDrive link)
EDIT 2 (next day) : after a disconnect/reconnect, and applying again the same tips as upper, no more (for the moment) twice times the link to my OneDrive personnal (I cross my fingers 🤞)