Ugh .. i wish things wouldn't auto update while I was already straining my CPU temperature.
Fortunately I'd saved my game 10 seconds before the system shut itself down.
Finally tried one weird trick:
Take another Windows box that has Google Drive on it, copy the files from Program Files\Google to the one with the broken setup, and run the uninstaller from Program Files\Google\Drivewhatever. Reboot.
Drive is now uninstalled properly AND my taskbar icons work again.
Created a new restore point. Going to try reinstalling now, and then going to bed whether it works or not.
Finally wrote up the saga of trying to uninstall and reinstall Google Drive for desktop after it crashed during an update, and my attempts to fix it making half of the icons on the Windows taskbar invisible, and what finally DID fix it.
And of course the installer that ran wasn't done, so it's in a state where the service won't run, won't uninstall, and won't reinstall. Even after deleting files manually.
I'm going to have to run regedit, aren't i?
Heck with it. I don't use this that often. I can pick it up another time and get back to my game for now