This specific problem — settling transactions — is an industry amounting to billions. Think of BTC like a MasterCard or Visa competitor, albeit a unique one.
I'm optimistic that there is a better way to store a ledger as you describe. Perhaps a database?
We've done this with a network that can process 400k transactions per day (at $20/transaction in fees), as compared to visa, which does 150 million per day.
Surely, we can do better?
It's clearly an industry with huge potential if it is economically viable to spend money buying an Argentina's worth of power on it.
As a whole people we should include these externalities in the value prop of services despite the fact that businesses and individuals don't because it's a cost we collectively pay.
Trash is my biggest pet-peeve example of this. As an individual I have very little power to control the amount of trash I produce because goods I buy come with so much stupid packaging that I can't give back or recycle and there is no incentive for the people in the position to affect change to do anything about it because they don't bear the cost.
In a similar fashion carbon taxes help to capture the negative externalities of energy use. And if the article is true then collecting that tax would make it so that bitcoin mining is (right now) unprofitable. This is to be expected since such a collection would be sudden increase in the cost of mining when the market has pushed margins thin. The market would adjust, transaction fees would go up, and miners would find non-carbon producing energy sources and we'd probably reach a new equilibrium that is profitable for everyone involved again.
If bitcoin went away tomorrow, a bunch of financial companies would have a lot of problems, a few big holders would be out money, and that's it. For every other human, it's Thursday.
Conversely, if gasoline didn't exist tomorrow, society would collapse.
But you posit that people choosing cigarettes provides some value, despite the negative effects. Why is there no value than in people being able to chose a money/investment vehicle they believe to be to their benefit?
Because the only thing generated is fake money on a spreadsheet. There is no product, there is only consumption of resources to generate nothing.
For all of what's involved here, you could just pull the same amount of money out of thin air, deposit it in their IRA, and nothing changes, apart from way, WAY less energy consumption.
Gold is one object that's served the money function in the past. It has properties (fungibility, durability, scarcity, etc.) that money needs. But it's "dumb" and cumbersome, as physical objects are.
Building digital objects that serve the money function is important. One solution is the centralized ACH/banking system. But this has drawbacks --- poor scarcity, high political exposure, etc. I view BTC as simply building a competitor. You get better money properties, at the cost of more energy, etc.
Is it worth it? I don't know. But that partly depends on how the future produces energy.