I don't think the first statement is strictly true. One of my favorite HNers uses F# for his startup. Microsoft is on DropBox's radar out of necessity. Chrome was first developed for Windows and still performs best on it.
The statement doesn't use any qualifiers. It uses the word "totally". One of the most common ways to take someone's opinion out of context is to make it sound black and white.
With the possible exception of the F#-using denizen of HN, the examples you mention are obligated, by the nature of their model, to exist on Windows. I would think that a better way to characterize whether they are on or off the radar of the relevant demographic would be to examine those cases where there is no such obligation.