Just yesterday, I overlapped a tiny terminal window (resized to be very small and set to "always on top") showing the current disk space ("watch df") over the corner of a larger window which was doing a file transfer. While I agree that non-overlapping panels are better most of the time, sometimes overlapping can be useful.
> treat my Google Drive as just another folder
That illusion would fail quickly as soon as your network connection dropped. Non-local folders have fundamental differences to local folders and should be treated differently. (Local folders can be assumed to always be present unless manually removed, be fast, and unmetered; non-local folders can disappear and/or change at any time, can be slow and/or vary in speed, and might have a per-megabyte cost.)