Wow, that's a brain flipper.
Let's see.... Well ...
I dunno. I'm saying paper money will die and he says it won't. I think you're right: it's up to me to give the timeframe. I will say it dies in the next 50 years.
But he said it will NEVER die... Effectively. I think it's bullshit to say never
Well never say never. I wonder if debit cards will disappear. All they really are is proof you are who you are. In the future, maybe we will put our eyeball into some thing that IDs us by a retinal scan, thus authorizing the transaction.
In the Netherlands, banks charge merchants for using/depositing paper money. So if you try to use cash at point of sale there's a fee for the customer.
Still, we're looking at this through a very western-centric prism. There are countries where people don't carry around debit cards (or retinal scanners, lol) and are more "backwards" as far as their monetary transaction technology. It would screw them over to eliminate the greenback (or the Queenback, and other western currencies). In Japan, few people use debit or credit cards outside of the city; and checks are practically unheard of. (I read this in a recently-updated Japanese language textbook.)
I have to say though, it might be better for the blind and visually impaired to get rid of paper money and coins. Many countries either don't have different sized notes for the blind, or constantly change their size (again confounding the visually-impaired). Using my hypothetical retinal scanner, or a more advanced type of debit card, the price can be repeated by computer voice at point of sale. No scamming them any more ("Sorry ma'am, you gave me a five, not a fifty..." etc.)
The down side to eliminating real money is that transactions will no longer be private. Governments and banks can see exactly what you are doing all the time, which means handing over to them the power over our own private wealth. And of course, banks will find a way to work this to their advantage (profit).