Earlier quoted context omitted.
I don't know that RyanZAG is so much being user-hostile as reminding us that there are facts of non-free systems that are going translate to user-hostile for at least some subset of users. There's incentives for people who make closed systems to make the most common edges of them comfortable. There's also incentives for them to ignore other sharp edges or to even actively make other edges nearly untraversable.
I came here to say exactly this. Source: I work in the guts of some of the biggest telecom networks on the planet. Federation is a problem because none of the standards interop. The closest thing we had was XMPP which became mega-bloatware as time went by and is now just not something anyone wants to implement (and it's becoming less of an issue as most of the players move away from open-ness). While the technical am…
We got number portability and wireless number portability, but the carriers still act as if they own our e.164 addresses and make the transfers arbitrarily difficult. We use phone numbers of SMS, but really we use individual address books, stored in devices, or synchronized with central repositories. We use names to identify people and have to work hard to ensure that our address books are not filled up with duplicates created because we used a one-off email address, or phone number and the phone wasn't able to merge it with an existing contact automatically. We have identity providers that can only represent a small portion of our identity, real names on Facebook and Google+, but cannot resolve that back to our phone numbers or find the best way to contact us at any given time. Presence, which was the real promise of IM and XMPP (and SIMPLE if you must) is not integrated. I cannot determine before hand whether somebody is available to talk on the phone, would prefer a text message, or if I should leave a push voice message they can listen to at their leisure.
Even calling a company with a well designed IVR is still a confusing waste of time, when the device I am calling that system from is smart enough to contain any identifier or proof of identity that the called party would need, the protocols are artificially limited to phone numbers as identifiers. There is also no out of band solution to this problem, or the the problem of selecting what department I would prefer to speak with about a problem without navigating a menu that the interface on my device is not really designed to use. Think DTMF on an Android device where the screen shuts off.