Regarding the last. I didn't say that Bitcoin is useless, but dumb. Bitcoin is used as a get-rich-quick scheme, some kind of unit-based pyramid scheme. But as a concept it is dumb. It spends energy on managing empty units. If you wanna buy an empty box for $70K because you think someone else will buy it for $100K that's the scheme. But if someone spends enormous amounts of energy to run such a scheme that's dumb. Of course, calling that empty box a valuable asset, comparing it to gold, or suggesting it is the future of postal services is dumb as well.
We let you be with your thoughts and ideas and we will have our own. We can't and don't want to convince you that Bitcoin is something useful and worthy and you shouldn't try and do that with us because we feel your arguments are dumb and not Bitcoin or the fact that energy is being used to run it.
A lot of energy is used to produce a lot of products in the world, are all those products useless or is it dumb for the companies to be using so much energy only to create a materialistic thing such as a doll or anything in general which doesn't serve much purpose but is created because it is sold and they earn money for it. So your arguments don't really make much sense.