Force SharePoint Online Folders to sync through OneDrive to clients via GPO
Now that you allow users to Sync SharePoint Online Folders to OneDrive. You should make it so an admin (through GPO) can set a folder to sync to client machines. So if an admin wants to have files always available to the client they can be pushed through OneDrive and GPO.
Michael Mardahl commented
I solved this by means of a user logon script. it can be modified to access sharepoint libraries that are not Office 365 Groups. Please have a look and comment in the bottom if you have specific requests: https://www.iphase.dk/auto-mapping-office-365-group-drives-with-onedrive/
It could be a GPO and/or GPP so that admins can copy the link for the library or libraries that user needs. This way makes provisioning easier and better for those cases of departmental libraries that user needs. in addition to this the default behavior could be to keep files in the cloud and create an option to sync files.