This is a niche article, where it reads as though the SMS 2FA messages started coming through right as the lady purchased a cell service. Well the lady would have needed to have activated 2FA first and walked away from the house to even enable it.

Then goes on to say that TOPT is also too difficult, firstly because you have to download an app to do it, yet she supposedly knows how to use her phone.

There will always be edge cases where something doesn't work perfectly the way it does for everyone else. The solution here seems to be help her choose a TOPT app, print out those backup codes and be done with it.