You're not far from the truth.
Companies as big as Microsoft are entire ecosystems of opinion and endeavor. It's easy for one department to be developing an open-source extinguisher while another genuinely embraces the community.

It is only when an observer (e.g. high level management) really evaluates these respective ventures that one could ever become an "official" stance.
And really, the likelihood of said observer actually applying time and mental resources to something as amorphous and non-deadline as "supporting or killing open-source software" is rather slim. So bureaucratic limbo it is.