I think you are severely underestimating the "average traveler", and especially a family. Some folks go on vacation to get away from things, and for a foreign visitor, not having network access is sometimes a good thing. Also, many folks here in America have phones that will deal with calls and basic WiFi, but not network access. Of course, the odds are less when you charge over $100 just to enter the park, but still, how about a family, will they split up and how, will say Dad and the little ones go ride Autopia, while Mom and the larger kids go ride Matterhorn? What if they have one phone?
And as others have mentioned, two big issues, one is Disney and its problems with tech, and the second is Network access, during my recent Christmas visit, it was impossible to get a decent Network signal while waiting for the fireworks and the parades, since so many folks near me where trying to do the same thing (aka killing time while waiting for the event to start). How will the networks handle the onrush of users at Park Opening?
And then there is this "have to be in the park" thing work, yes, there is spoofing, but will specific rooms at the GCH suddenly now become more valuable than others, since it is on the edge of the park, and the system thinks they are actually in the park.
When will the system morph to add value to the Disney Hotel Guests, will they be able to access the system during Extra Magic Hour?
Lots of questions, and not many answers. So far, the best thing I have read is the GetAwayToday article about today's news (and of course, written with help from Disney Marketing, so the info, while not complete, is what Disney is saying about the upcoming changes).
https://www.getawaytoday.com/blogs/2017-01-11/everything-you-need-to-know-about-the-disneyland-m