The issue you describe most commonly happens to free (Gmail) accounts. Drive File Stream is only available for GSuite customers, and even those still have the option to continue using Backup and Sync (which is the Google Drive replacement for free accounts, and keeps syncing all files).

I just switched to B&S (to migrate to a new laptop): R(estore) is missing! I have to manually download my backup, and manually move files back to their original location!

This is a weird backup tool.

Here are the steps for restore (although they can be terse)

1. Install Backup and Sync on new computer

2. Add an empty folder "Temp" to backup

3. Let the folder be backed up so that a Computers > My New Computer > TEMP is created on the cloud.

4. Go to cloud and move the top level folders in Computers > My Old Computer > Documents/Downloads/etc into Computers > My New Computer

5. Create empty folders with the same name on the new computer.

6. Add them each in the Preferences. In version 3.36+, the application will recognize that it exists in the cloud. It will then tell the user it will merge the folders.

7. Uncheck the TEMP folder you added

8. Click Apply

All your content will be downloaded.

Yes.