Can someone explain to me who these people are? What were they doing before they’ve been ordered to DC? Are they a standing army, training while they’re not ordered somewhere? Or are they reservists? Or police from elsewhere?

Yes exactly. Embrace and extinguish has always been Microsoft’s strategy. They’ll release their own distribution and either make it slower and more complicated than Windows, so that everyone thinks Windows is the better OS, or they’ll make it a cloud OS like Chrome, requiring recurring payments to use Office 365 and everything else.