Nonsense. You can mount filesystems to mount points in much the same way as is done in Unix. No one would ever need to do that.
You can indeed use mount points like C:\mountdir, but that's still on the C drive, which is a drive letter. It's not "no drive letters".
You can indeed use mount points like C:\mountdir, but that's still on the C drive, which is a drive letter. It's not "no drive letters".