It's interesting, but they failed to take in account things like Layer2 solutions built ontop of the blockchain.That's my point. A wide-scale adoption of crypto currencies would lead to a massive reduction in the monies available for governments to fund public services.
Just like what happened with gold, people would start to hoard bticoin and the whole economy would dry up.
Very interesting article here....
https://www.fastcompany.com/40537404/how-bitcoin-ends
I'd also point out that bitcoin is divisible by 8 decimals so there is really not much of a shortage should it ever take over as the primary global reserve currency.