Do you have some modelling, or any credible reference to back up your assertion that the energy used by banks would be higher than a Bitcoin blockchain?
Even if I did provide you some report showing banks use more than Bitcoin (which is still true for now) it's only a fraction of the big picture. Although banks are a good example of this effect, Bitcoin doesn't JUST improve banking. As this plays out, mining infrastructure provides a shared resource that can be used by MILLIONS of companies, among which are banks who manage massive datacenters requiring humans and their associated energy consumption, the cost for audits, compliance, card readers, and other things that Bitcoin makes effortless. Surely unlocking efficiency offsets power consumption, and at scale the efficiency improvements can be astronomical. An accurate figure on this probably does not even exist, especially considering the lack of imagination with respect to Bitcoin use-cases. Not to mention the biggest energy consumers are also the best in the world at reducing their consumption out of competitive necessity.
And if so, would you provide a projection for the relative energy useage of traditional banking vs. bitcoin for a linearly expanding money supply extended out indefinitely?