The iPhone launched with a phone, email and an internet browser (not limited to the mobile internet) in your pocket. I think those were the killer apps, where each one had already proved their value in other form factors.
I think part of the focus on apps is because while portable connectivity is an easier feature for most people to understand and appreciate (though I appreciate this may not have been quite as clear in 2007), wearability is less so, especially where the form factor is socially and ergonomically awkward. Working in AR/VR I know my team is constantly asking variations of "how can we convince someone to put this on their face?" My interpretation of pieces like this is often that they echo underlying concerns over the efficacy of use-cases, and decisions by players like Netflix to port their apps is some (albeit noisy and incomplete) data around it.