It still offends me. A lot. That everybody still has phone numbers. And for more than just interfacing with legacy POTS land lines. It bugs me that a mobile phone isn't a mobile computer with a world-routable IPv6 address and that voice communication isn't just a special case application that runs on top of this.
It's even more annoying that programs that run over IP and don't use the non-IP parts of the mobile network still insist you have a 'phone number'.