Comparing the energy used for Visa transactions to Bitcoin is a false comparison. Bitcoin not only handles transactions, but more importantly, it maintains current wealth and the entire history of every transaction that took place, including the rules that manage it.
You should compare the energy bitcoin uses to all energy used by traditional banks, their corporate headquarters, the government regulators responsible for managing the system, lawyers / judges / institutions managing conflicts, mobile apps and servers powering it, etc.
Bitcoin is doing all of these things without formal institutions, employees, governance, and official regulation.
You should compare the energy bitcoin uses to all energy used by traditional banks, their corporate headquarters, the government regulators responsible for managing the system, lawyers / judges / institutions managing conflicts, mobile apps and servers powering it, etc.
Bitcoin is doing all of these things without formal institutions, employees, governance, and official regulation.