Just a spitball idea, but rather than focusing on the consumer market, they could've been the new blackberry for businesses (that give employees phones). Native active directory and group policy integration would be a good solution for the myriad of third party apps/services/devices that attempt to control the other phones.
For sure. Enterprise mobile was not really a thing back then. (Laptops with VPN was state of the art.) Microsoft could have organically owned the enterprise mobile market but chose not to.