Do those users use the desktop shell at all though? In my experience with novice users (across platforms: Mac noobs are no better) is that they only know enough to launch apps. They never touch the desktop integration at all.
Their old MacOS Finder was clear and simple - my wife would spend hours arranging her work in coloured folders, each of which opened in a window whose shape and position she had chosen, and was meaningful to her. It was a powerful tool that enabled her to arrange and group her work.
Now, both Apple and Microsoft compete with each other over how bad they can make their file system interface. Microsoft wanted to do away with the filesystem in Longhorn, and Apple have actually done so in iOS.
Is this progress??
You're absolutely right. I don't have the citation on me right now, but spatial mode has been found to be easier to grasp for new users in every single test ever. The only reason it was dropped was because (1) Windows Explorer, (2) power users whined about too many open windows and (3) a lot of people got used to URLs opening in the same window thanks to web browsers, so people sought to apply the same principles to file browsers.
Spatial mode used to be default on GNOME for a long time. There, too, it was dropped because of the same reasons.
See also: http://en.wikipedia.org/wiki/Spatial_file_manager and http://www.bytebot.net/geekdocs/spatial-nautilus.html
The problem is that there's no global switch to force Finder in spatial mode coming from anywhere, anytime. This results in a messy affair when suddenly a non-spatial Finder pops up because you never opened that folder directly and previously put it in spatial mode.
You can easily have two Finder windows open on the same folder, meaning you lose the immediate recognition that spatial mode gives you. My personal take - they should have two types of Finder window - a spatial "folder contents" window and a folder-browser (probably in column-view) that only shows folders and maybe a preview of the files within.
So you can navigate quickly/enter file-paths in the browser, but to actually use a folder, you enter spatial mode, so you have the instant recognition of where you are.
Wonderful though Linux is, it's applications are not consistent or mature enough to support a totally document-centric UI. Microsoft could achieve that with Office, but they would probably be accused of over-integration, and hit with the anti-trust stick.
Disclaimer: I believe the best UI for a filesystem manager was Windows Explorer 98, the last iteration with perpetual, irrevocable and non exclusive root access, with Norton Commander as its only rival.
From the moment we cared about maintaining our system's safety from the user's "big fingers syndrome", it all went down (starting with hiding file extensions) to the atrocities we now have to deal with. And yes, I put Seven's Explorer in the same basket as Finder and the likes of Nautilus, mostly due to /that/ horrible folder scrolling bug that MS refuses to hotfix.
All of those actions require knowing how to [delete], [open folders], [drag and drop].