In my experience both as a user and as a contributor in various forms for well over a decade, I have rarely if ever met a single person with a anti-MS position as the primary reason to use FOSS. They might exist but certainly a fringe element. I have seen freedom, flexibility and several other reasons commonly cited and that has nothing to do with any single organization. Reducing it to such low levels is a sham and a poor one at that without any evidence to back up such claims.