2. High consumption of electricity in running the network etc.
What is the problem here? The banking system uses a lot more electricity, yet people never complained, not even ecologists. Most of the electricity to mine comes from renewable energies. The energy that would otherwise be lost: even if there is no demand, the sun continues to shine, it doesn't care if you need electricity.
This is exactly right. I'm sure most of the arguments are well-worn but I outlined a few in
The Currencies That Are Killing Our Planet.
Fiat not only consumes more energy in its birth than bitcoin mining (11 terawatt hours versus 8.27) but fiat is doubly damaging at its death, when it must be destroyed by burning, releasing even more CO2 into the atmosphere.
A 2010 study by Ahlers found that the printing of the U.S. dollar alone used 3,530 tonnes of ink, over 7,100 tonnes of cotton and 2,300 tonnes of linen. Waste products from its manufacture include a total of 2,720 tonnes of pulp and ink sludge.
....the power use of bitcoin mining expressed as a percentage of global energy consumption is only 0.13%.
The whole 'high energy consumption' meme regarding bitcoin and crypto is just another attack on BTC similar to and with the same kind of validity as 'but criminals use it'.