I agree with nearly everything you said, but I disagree, fundamentally, with the bolded. Gold mining is not a waste of energy. It is the opposite of waste, it is the measure of value people place in the 'utility of having gold as a medium of exchange' or a store of wealth, jewelry around their body parts or connectors on their home theater system. If there was no demand for gold, the price would be zero. Hence it is not a 'waste,' by definition.
Not necessarily, digging out a little bit more gold just makes the existing gold a bit less valuable since the supply is increased. That is because its value is mainly derived from its scarcity. Its utility IS its scarcity. However, it is not a waste for the miner if the cost of mining can stay below the price of gold.
I really I understood the point of this thread but I guess I didn't.
I assumed that if you could design to do the exact same thing in the same commodity quantities and at the same protection level, BUT consuming less energy and producing less BTUs of heat, then that would be less wasteful.
You can mine gold in lots of ways, some require less resources than others. If two processes produce the same amount of gold then no point in optimizing anything else?
I suppose that if anybody (as opposed to a single trusted entity) can produce bitcoins then the production costs will converge close to value of the produced bitcoin itself. If that were not true then it would make sense for someone to invest resources to produce as many bitcoin as possible. Since we dont want to let the value of bitcoin to go down then the production costs need to rise to the value of bitcoin.