Even if Bitcoin actually became a valid means of transaction and bank branches, ATMs, etc became obsolete, it doesn’t replace the need for trading floors as an interface between finance and equities/commodities, so that’s a weird comparison.
But even so, I wouldn’t be so confident that the banking sector uses more, or will for long given the current investment spree into mining. Here’s one plant that will use nearly 4x the energy of downtown Dallas:
https://www.cnbc.com/2021/10/31/bitcoin-mining-giants-bitdee...
Mind you, the more the price of Bitcoin goes up, the more energy miners burn on mining, so if Bitcoin actually grew to the size of the fiat economy we’d be talking about substantially more energy use.
You are not taking into account the diminishing block reward. More and more miners are chasing a dwindling supply of coin and will eventually only earn transaction fees and no block reward. This will put a natural dampener on more miners coming in (all other things being equal) and it will plateau.
Bitcoin is just additional, unnecessary carbon and e-waste on top of the existing economy. It's fatal flaw is that it's deflationary, which in a world of rational thinkers would have doomed it from the start, but instead it seems to have attracted those yearning for a system free of "money printers".
Inflation can make things bad for an economy. Deflation utterly destroys economies.
(Even more so in the third world, where quite a few people have personally lived through periods when government printed money like crazy, and saw first hand how it starts and how it ends.)
Hyperinflation is just a symptom of other broken things in those places, and the real solution is to work on that brokeness.
You don't paper over lack of trust with a system that sort of works around lack of trust, you increase trust. Otherwise you'll be screwed in a million other ways that have nothing to do with money.
It's all well and good to talk about fixing brokenness, but it's not always politically viable. Furthermore, even when it is, people still have to go around living in the meantime. "It'll be solved eventually when everything is made perfect" is not a reasonable approach, and people are well aware of that. A very popular saying where I'm from goes, "the strictness of the law is mitigated by not having to follow it".
What you want is a monetary system that is inherently trustless.
Let the policy makers deal with policy and legislation. But let's not let them mess about with our money any more. Anywhere.
Everything has a cost. But is the cost worth paying is the question.