Ethereum developers have been working extremely hard to move to proof of stake to remove this massive power requirement. It's too bad that wasn't mentioned in the article.
Also, most currency transfer being digital is a non-sequitor Businesses still need to move the money from their location to the bank regardless of the volume of transfers done digitally.
https://www.vice.com/en_us/article/ywbbpm/bitcoin-mining-ele...
There is energy in certain places (underground, hydro) that cannot be transported to wherever journalists are writing their papers as they spitball electricity calculations.
https://news.bitcoin.com/how-big-hydro-power-partners-with-b...
China’s southwestern Sichuan province, a mountainous region that is estimated to have over 50% of the Bitcoin network’s total computing power
https://www.coindesk.com/bitcoin-mining-hash-rate-rainstorms...