Am I the only one who is frustrated by the plethora of operating systems available for x86? Why not just have just a single, highly customizable and secure desktop operating system instead? Is there any sane reason for having so many[1] mainstream OSs?

[1]: FreeBSD, GNU/Linux, NetBSD, OpenBSD, Windows, Minix, OSX, Solaris, are the ones I know off the top of my head