It is what is making it economically viable to develop this energy source. If the blockchain is a waste of energy as you say, then when it becomes worthless the

It is what is making it economically viable to develop this energy source. If the blockchain is a waste of energy as you say, then when it becomes worthless the infrastructure will exist to produce this energy and use it for other purposes such as PC gaming and ironing shirts. Without it though this energy source wouldn't exist, so why not let the dumb people get duped into paying to produce renewable infrastructure? And if it turns out it's not a waste of energy and you're wrong, all is still well. It's a win win.