There's nothing in the commercial, actually, that depicts ordinary, routine phone calls. They're intimate conversations between people with deep relationships to each other, who are separated and cannot be together – sometimes at critical, god-I-wish-I-had-a-teleporter moments.
If you've felt the kind of deep longing that sort of separation can cause, you'll immediately understand what Apple is selling here. A lifeline to the ones you love.
Believe me, at those moments there's not a chance you'd rather just be on IM.