Why is that? I'm not sure why the presence of a headphone jack on the MacBook Pro should translate to USB-C on the iPhone. Even though USB-C is widely available I'm pretty invested in lightning at this point. I have a bunch of accessories, dongles, and no less than a dozen lightning cables.
Now, if you're talking about the lack of traditional USB on the MacBook Pro and the fact that the cable that comes with the iPhone won't actually work with USB-C, then I somewhat see the argument here.