BTC has pivoted away from the Bitcoin whitepaper in mid 2017, decided to constrain its transactional troughput and went the "store of value" route. It can handle some 4 transactions per second.
An unconstrained version of bitcoin can handle hundreds, and with technological improvements thousands and then tens of thousands of transactions per second. I can already do this on a Raspberry Pi [0] (in controlled conditions).
Bitcoin's footprint is sadly big, but still smaller than that of the banking industry. I foresee a future where most of the mining is done with renewables, as this is what will make the most sense.
As I said, the number of transactions is irrelevant up until the block reward gets minuscule or completely ends. That is statistically not expected to happen before a few decades.
I know about the banking industry argument but the banking industry is not only about transactions and they also catch up with technology, removing staff closing down offices and branches. In fact, those related to transactions are already almost gone, the rest is about things where BTC is irrelevant anyway, things like compliance anti-fraud etc. If anything, the crypto exchanges assumed many of the banking infrastructure.
Blockchain vs a centralised database is not even a competition when it comes to efficiency, no matter how much you want o twist the argument the fundamentals are rock solid.
What blockchain solves is the trust issue but only for storing the value and not for using it. The problem is, we as humans rarely transact with people who we don't trust. Even with the ransomware and drug trade use cases of the crypto coins, the transaction depends on the trust that the seller will deliver the goods.
The only possible use case is when the society ceases to function. When that happens, BTC would be very useful but when that happens the economy would be fraction of what is now because everything beyond transactions will still need trust so that the labour can integrate vertically and do high value production.
If bitcoin had the same market cap as all of the cash in the world (around 40 trillion) the price would be higher and the ecological footprint would be significantly worse.
An unconstrained version of bitcoin can handle hundreds, and with technological improvements thousands and then tens of thousands of transactions per second. I can already do this on a Raspberry Pi [0] (in controlled conditions).
Bitcoin's footprint is sadly big, but still smaller than that of the banking industry. I foresee a future where most of the mining is done with renewables, as this is what will make the most sense.
[0] https://read.cash/@mtrycz/how-my-rpi4-handles-scalenets-256m...