Iger's response did give some answers in that regard.
If they opt out of the MagicBand, the other option is an RFID-enabled card. It can pretty much do all the touch-and-go stuff the MagicBand can do. It won't allow for some of the location-based experiences though that the MagicBand can trigger with the longer-range transmitter, since it lacks it. Exactly what this means, we don't know, but it is likely the dynamic/custom experiences that have been touted:
Now, as far as opting out of MyMagic+ completely:
After re-reading these sections, it does NOT imply that FastPass+ would not be available, but there is the implication that FastPass+ advanced reservations could not be made, since using the
MDE website or app is in essence opting in to MyMagic+. Whether any day-of FP+ options will be available is a whole 'nother ball of threads, and whether it is accessible if you don't at least provide a name and email address is unclear, which some people may still choose not to give - or for that matter, have.