That one has always puzzled me. The first Linux program I downloaded separately from Debian (whose collection of packages used to be small enough that you actually did that from time to time) was Star Office 4.0. With which I manipulated Office files.
It wasn't Free at the time, but it was free. And though it didn't save a Free software zealot from the impossibility of manipulating Office files without proprietary software, it did at least offer a way to do so without an entirely proprietary operating environment.
'fraid I'm too much of a kid to recall the "unstable" argument. I started switching my primary desktop into Linux when I noticed that my computer never crashed when I was in Linux instead of Windows :)