Yes one drive replaces the default path locations with its own onedrive locations but the local folders are still there under ~/users/user/Documents etc. Also Disabling onedrive doesnt delete the copies, they are still there in microsoft cloud the user needs to go grab them. The users are using a tool that moves unused files to the cloud, its expected that they take the necessary steps to reverse that when they stop using that tool. You cant just disable onedrive and expect everything to magically be downloaded back unless you click the download all button or go to the website.
The issue is users dont know how it works and dont want to know. I dont blame them since microsoft is so dogshit at ui/ux to the point where its malicious.
No because they would go to the download folder which isnt synced with onedrive.
Yes this is the biggest issue with onedrive but its still on users to administer their system at the end of the day. That means doing the bare minimum research when removing something as integral as Onedrive. You cant just turn off a home directory sync service and not make sure your stuff has been downloaded out of that service.