As I see it, the debate revolves around that the idea that the freedom of the internet is being siloed by operating system developers in thier 'App' platforms.
The internet was once a free thing, freely available, freely created, freely consumable from just about any device that implemented a method to consume or edit HTML: from Lynx to Mosaic to Chrome, it was there--in some form--for you to peruse and create. Apps change all that, now experiences with the world wide web are being contained in siloes, be it Apple's or Google's. There is something lost in all of this, and it is our duty to remain cognizant of it and vigilant in the world wide web maintaing its accessibility for all, even those without smartphones or fancy tablets.
I'm not saying we are forgetting where we came from, many of us aren't--but there is a threat, a concern, that this freedom is being corrupted.