Short bio: Computer Scientist, FOSS supporter (read more)
Tux Machines (TM)-specific
When you see your business model threatened, there are two options: confront the problem, change strategy and adapt to the new situation or, if you are powerful enough, try to destroy the threat.
For Microsoft and other companies living off charging for the use of their applications, free software is a problem, because the idea of programs anyone can use for free is a torpedo aimed at their established business model. Accusing free software of a variety of sins –amateurish, expensive, unpredictable, anti-American, even communist– buys them time to reconsider their model.