OSX may not be open source, but isn't it built on top of BSD and doesn't it include/use a lot of open source software?
What's important about this isn't so much that free software didn't fail, but that modern computing could not and would not exist without free software. End of story. Mac classic would be all but dead now, and Windows would have "innovated" us all in to a ditch. Remember what Microsoft did to IE when Netscape wasn't a threat? It'd be the same story. Without free software, there wouldn't be a mozilla, an OSX, or anything like it. Modern computing absolutely requires free software in order to function.