Unity and Gnome3 have virtual desktops, just not the best functionality. You either do a key-combo or move the mouse to a hot corner, pause, then it shows a sort of tiled or thumbnailed view of each open application as if it was on it's own desktop, and you click on the one you want and it then fills the screen.
Instead of behaving like multiple desktops, it's more like a slow way to maximize the application window you want to use next It's almost like the Windows Alt-Tab/Alt-Shift-Tab maneuver to scroll through to the next or previous open application windows.
What I was describing in XFCE is how you switch workspaces.
I work best with 3 virtual desktops on my laptop and 4 on my desktop, and the XFCE desktop environment has the best tweaks built in - that is, switching to the next desktop can be done by mousing past the edge of the screen. Of course you can click your chosen desktop in the indicator applet in the panel, and I'm sure there's a goofy key-combo that will do the same thing. But having a super fast target 1080 pixels tall at each edge of the screen is unbeatable. Application windows are always maximized, they never have to take turns sharing the same screen.
In Gnome2/Mate desktops, this switching action isn't built in, but available with the "brightside-properties" package. Brightside-properties also worked on the early Ubuntu Netbook Remix, but since Unity/Gnome3 came along it doesn't work in those environments and I've found no way to make it happen.
Although Windows didn't do virtual desktops, at least they didn't stand in the way of OEMs making their own desktops. My first pc was a Win95 Sony Vaio (200Mhz, 32MB RAM!) and Sony had some sort of desktop mask that would allow you to have a ridiculously huge desktop, like 4096^2, but it was windowed to whatever 800x600 section you felt like seeing at the time. It rocked! It's was better than what Gnome3/Unity have become now, 15 years later.
