Dear Xamie,
Thank you for posting your query in our community.
Per your description, you can't delete the OneDrive sync folder after unlinking your account.
Generally, after unlinking OneDrive, if you don't want to use OneDrive, you can right-click the OneDrive sync folder to delete it manually.
May I know that whether you get any error message when right-clicking the OneDrive sync folder to delete it? If yes, to help you better, could you please provide the screenshot of the error message for me?
Sincerely,
Jazlyn | Microsoft Community Moderator
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