Before you point the finger at Cryptocurrency lets consider fiat...
Carbon footprint for fiat and fiat infastructure...
Physical bank locations, redundant across the globe several in most every town... Having to construct these said banks, heat and cool and maintain them. The paper and other resources they consume..... Also that real estate could be used to organically grow food, or left wild to sequester carbon ...
The emissions and resources used from people driving to and from these physical location... Customers and banking infrastructure requires an enormous amount of energy and resources transporting the physical dollars...
3.The fiat minting process uses an incredible amount of energy and resources.
As for Bitcoin and cryptocurrency yes its mining is rather wasteful however comparatively much less so than fiat.. There is also more cryptocurrency available than BTC some using much less energy to mine.... For example BURSTcoin