This is definitely not the case. The .Net Foundation is not staffed by Microsoft, nor is it owned by Microsoft. It’s an entirely distinct entity though I believe some board members work for Microsoft.
That’s where the poor & questionable transparency comes in, they try to market it as independent but it was formed and funded by Microsoft with the Executive Director whose performing all the objectionable actions an MS employee who is also the only person that is able to approve all material changes made to the foundation whose position can only be filled by the founding member who is Microsoft, in effect they are the silent hand making all the power moves to its member projects without their consent, wishes or even a courtesy notification. Then to try downplay the bad PR you had the MS VP Director with no visible ties to the foundation willing to jump on a call to disgruntled members so they can downplay their MS foundation employees actions behind close doors.