Microsoft is focusing on the enterprise, because that's where the money is. For example, CERN is using Microsoft Lync as an IP PBX, using the Polycom CX300. It looks like a desk telephone and works like a desk telephone. It can even retrieve voicemail. But it plugs in to a USB port and uses Lync for calling. https://espace.cern.ch/mmmservices-help/UnifiedCommunication...

It's a lot simpler to sell to CERN and pick up 2500 users, than to sell to 2500 different barbershops. For one thing, CERN has competent IT staff who won't be costing Microsoft a lot of money in support calls.

As for Google, they seem to actively be avoiding telephony. For example, Gizmo5 used to offer SIP connectivity, and then Google got rid of Google Voice forwarding to Gizmo5. And now the elimination of XMPP and the option to use Obihai. Even Google Fiber was set up as a double-play instead of a triple-play: they'll sell you Internet and television, but not phone.

I get the feeling that Google wants to make absolutely sure that it is not regulated as a telephony provider, with all the hassles around 911, service availability, being able to call high-cost rural exchanges, etc.