However, the “removing barriers to entry” logic is why it’s actually good for the free software desktop to have Firefox and OpenOffice.org on Windows. What’s more likely – an organisation switching their OS, browser and office suite all at the same time, or one at a time? If you don’t have to change your apps, switching to the cheaper, more secure, more stable OS is much more of an easy move.
But Aaron is half right. If we have killer apps on Linux for which no functional equivalents exist on Windows, then porting them would be a bad idea. Firefox and OpenOffice.org have well-established competitors on Windows, and so having the free software equivalents on Windows has no downside. This is similar to the logic rms suggests people use when deciding to license a library under the LGPL or GPL:
The most common case is when a free library’s features are readily available for proprietary software through other alternative libraries. In that case, the library cannot give free software any particular advantage, so it is better to use the Library GPL for that library… However, when a library provides a significant unique capability, like GNU Readline, that’s a horse of a different color. The Readline library implements input editing and history for interactive programs, and that’s a facility not generally available elsewhere. Releasing it under the GPL and limiting its use to free programs gives our community a real boost. At least one application program is free software today specifically because that was necessary for using Readline.