Then it's still using up renewable energy that could have been used on something else. Electricity is mostly fungible.

This is decidedly not true. Electricity transmission has substantial losses over long distances. Check out this article for more information about how the crypto mining industry uses electricity.

https://hackernoon.com/the-reports-of-bitcoin-environmental-...

Energy is a product on the market. Whoever wants to pay for it is free to do it, what’s your problem?

Besides you seem to be missing one important fact about energy - it is very expensive to store much of it, which is why many bitcoin farms use up available excessive energy because that way it makes them more profitable and the grid more stable.

> Energy is a product on the market. Whoever wants to pay for it is free to do it, what’s your problem?

Carbon output, on a global scale, which is already hard enough to keep under control. We don't need yet another massive source of energy use, particularly one that gives us virtually nothing in return.

How is electricity fungible? Conductors waste power proportional to the distance.

Bitcoin, like aluminum before it, can be used to "export" electricity from places where it's cheap and hopefully renewable, like a hydro power plant.

No it doesn't fall over as long we are still making "dirty" energy, which we absolutely do.