If you're in rural India and don't have access to a bank account, but you do have internet access via a smartphone, then I could definitely see cryptocurrency being valuable to you. And that doesn't even take into account countries like Venezuela that are experiencing hyperinflation, where cryptocurrency would be much more useful. There are cryptocurrencies that are energy efficient and have low (or even zero) transaction fees. I doubt the author has looked into these coins.

Beyond just currency uses, smart contracts open the door to phasing out escrow middlemen for purely digital transactions (like buying/selling domain names, etc.) Decentralized lending and borrowing is another major use of smart contract coins.