This isn't exactly helpful if you don't have a data plan with your phone, and a decent amount of people don't. In fact, it kind of places you at a disadvantage if you don't have a smartphone. I feel like my ability to use Fastpass is diminished, compared to previous trips, because I don't have a smartphone. It sounds like it will be harder for me to get a Fastpass now and that I'll have wait in stand-by more often.
You're exactly right. For instance, there's nothing difficult about reserving a Fastpass+ online; we've all been making ADRs for years. But I have no interest in deciding what I want to ride and when before my trip. I don't want my vacation to be that regimented. Incidentally, the advance ride reservations are one of the reasons I do not plan to return to WDW for the foreseeable future.
Furthermore, payment and room access via MagicBand...is this really that big of a deal? It's not like any of these things were difficult before.