Maybe he did not deliberately log into one drive, but was tricked with dark patterns and suggestive interface design. Which makes it even worse.

Or maybe he in fact is not logged into onedrive, and 365 simply sucks.

Actually I am not logged on OneDrive (AFAIK I did not create any OneDrive accounts) Excel insists that I should save my spreadsheets on OneDrive. Thus the infuriation.