The author severely overestimates how much of a risk the iPhone was for Apple, and how unexpectedly it changed the way we interact with mobile devices. He is forgetting the iPod Touch, which was Apple's "concept" model (that actually shipped).
If the response to the iPod Touch wasn't as positive as it was, the iPhone may have never been released, or would've been delayed until a few more iterations of the iPod Touch product line.
I'm having the unpleasant sensation of my neurons rearranging themselves to account for the realisation that my memory of the relevant events was so fundamentally incorrect. I do apologise.
I'm fairly new to commenting on HN, is it bad form to delete my comment to avoid the downvotes? EDIT: just realised that I don't even have that option anymore.
Back on topic - I think the iPhone was a risky launch. It was really unknown at the time whether it would succeed. I didn't think it would, but I didn't think the iPod would succeed either when it was launched in 2001.
If the response to the iPod Touch wasn't as positive as it was, the iPhone may have never been released, or would've been delayed until a few more iterations of the iPod Touch product line.