I listened to days of that Joe Duffy topic and have to say I could understand how some were caught, they were far from all elderly, one was quite young as in a college student who should be well up with technology.
I listened to many of the stories and especially the fact that the txts were dropped into the existing BOI thread of messages on phones, also BOIs t&c for online had a portion read out by one woman where it actually says they will contact you by txt if they suspect fraud on your account so in fairness no one reads the t&cs probably but the bank can hardly say now they don't send anything of importance on txt messages.
As an ex banker myself I was not on the bank's side in this one even though when the discussion started I presumed the people involved had all been careless but there was more to it than that, BOI knew the problem was going on for months and there was too much information available to the scammers, in some cases they had info on the accounts you would not expect them to have gained before actually getting to talk/txt customer. To be honest I actually really thought the scammers had some 'in' to BoI systems or info, now probably not and I presume we just have very smart scammers but it really sounded like a very insecure system.
I use online banking myself but never on a phone but then again I'm more old school and am working on a computer every day so it's handier to use it. Telling older people go to Post Office or CU is neither here nor there, not all are able to do this so online access is handy if they are able to use it, however it should be a bit more secure than having any scammer able to drop txts into a legitimate thread of txts from a bank or being able to make a call look like it's coming from any number they want. It it can't be made more secure then txt system should not be used for important stuff in my opinion. BOI in their statement to JD show (I think or statement to someone anyway) said they don't put anything of importance in the txt messaging system which contradicts the t&cs read out but if it's that unimportant why bother using it at all when it's a pathway for this stuff.