In a very real sense, our magic superpower is that we "giga-scale" with such low resource consumption, especially considering how large (in terms of parameters) the brain is compared to even the most advanced models we have running on those thousands of GPUs today. But that's where all those millions of years of evolution pay off. Don't diss the wetware!
Any suggestions on how to reduce that waste?
If you were able to somehow capture all that information in full detail as you've had access to by the age of say 25, it would likely dwarf the amount of information in millions of books by several orders of magnitude.
When you are 25 years old and are presented a strange looking ball and told to throw it into a strange looking basket for the first time. You are relying on an unfathomable amount of information turned into knowledge and countless prior experiments that you've accumulated/exercised to that point relating to the way your body and the world works.
What is surprising is that our brain, as complex as it is, can train so fast on such a meager energy budget.
Not necessarily so for the dynamics of magnetic fields, or nonhuman animal communications, or dark energy/matter.
We are bombarded nonstop by magnetic fields, nonhuman animal communications, and live in a universe which seems to be majority dominated by dark energy and matter, and yet understand little to none of it all.