One of the main appeals of a device like this is Linux, so I don't think a lot of people would like to have windows on a device like this, with only a keyboard and no built-in mouse/trackpoint/trackpad.
Furthermore, windows is scarier and scarier with each passing year, stealing data, displaying advertising on every page, installing automatic updates, etc.
It makes sense to have as many options as possible (and that is a great strength, if anything) but for the expenditure which I am sure it would require to get windows running on the Gemini, I do not think it is worth it.