Yes an FTTP model would have left the legacy copper intact and available for POTS. Though the Opex may make the maintenance of a wholesale network in order to keep POTS uneconomic
The storms after the major bushfires last year took out powerlines and there no power to the Telstra substation or the Telstra towers. The towers lasted a few hours but the the generators ran out of fuel. You would think that Telstra would have enough people around to refuel the gennnies but no. Would have been easier to train a local resident to do that and entrust them with the keys.
I use my Aldi sim in the mobile operated electric gate opener. No call charges because when I ring the gate, it will detect the caller ID and hang up and operate the gate. Basically the same tech as a mobile trigger for an IED.