You shouldn't be so surprised. The energy consumption issues of cryptocurrency are very well-known, and the claims that "you didn't take into account all the human office staff" were attempts to deflect discussion from this energy consumption, almost certainly made by nobody who ever attempted to crunch any numbers. (The last time I tried crunched the numbers, I noted that Bitcoin uses more energy than the US mint making literal physical currency in industrial processes, and that was with heavy overestimation of the energy consumption of the latter.)
Believing that taking into account human-associated energy costs would put them on rough parity would require assuming that computers take up 1/1000th the total energy costs. And that's before you actually look at how many human jobs would actually disappear were cryptocurrency to magically replace the financial industry.
Minting is probably the least energy intensive part of maintaining a fiat currency since paper is cheap. There is an enormous enforcement apparatus that goes into going after counterfeiting, keeping the mints incredibly secure, armored trucks to carry bills to destinations, etc.
Believing that taking into account human-associated energy costs would put them on rough parity would require assuming that computers take up 1/1000th the total energy costs. And that's before you actually look at how many human jobs would actually disappear were cryptocurrency to magically replace the financial industry.