In reading your post I thought of one thing: Google

You wrote: “What if, instead, the incumbents focused on ways to make the customer more sticky to a broad range of services? What if they offered cellular, land line, wifi, VoIP, and internet as a bundle, with a common user experience across all five? What if I had one address book, one email name, one phone number for every communications technology? ”

Except for the wireless and land line telephony, what are they not persuing? Add in “gdrive”, google calendar, etc and you can come up with some exciting scenarios.

BTW, I do own Google stock (10 shares).

Tom