Bitcoin wastes a lot of energy. I agree. It is basically a mechanism to turn energy into something analogous to money.
However, people do not generally live where there is a lot of potential to generate green energy. Wind, solar, geothermal, nuclear all generally work best far away from heavily populated areas (this is not always the case). Additionally, wind + solar are highly variable.
Per unit of energy renewable energy will always be more cost effective than fossil fuels in the long run, but there is a high fixed cost at present.
The more sources that can consume energy in remote areas the more incentives there are to build renewable energy sources.
Thus cryptocurrencies like bitcoin are a net positive for building green energy sources in the long term.
Energy is nof only used to “create” value, but also to hold it. Even when you reach the limit of 21 something milion bitcoins, every transaction will require a huge amount of energy, and the amount it requires will go up.