1) With electric heat you have to account for the energy production and grid transmission being around 30% efficient. Even though an electric heater or bitcoin miner is converting electricity to heat 100% efficiently, a majority of the thermal energy released in the power plant was already thrown out as waste.

2) Even using electricity, a heat pump beats the electric heaters. They're 2-3x as "efficient" in terms of how much heat it pushes into the house vs how much electricity it takes to do it. Technically this is measured as "coefficient of performance" instead of efficiency, since it's a ratio of heat transferred / energy consumed, rather than energy released / energy consumed (and efficiency >100% wouldn't make much sense).

3) Gas furnaces can be >90% efficient, which also beats the bitcoin miners. Even the lowest efficiency allowed by law (78%) is better than resistive electric.

4) There's more "embodied energy" in building a bitcoin miner than an electric heater, and it has a very short life as a useful miner before it's obseleted by newer chips.

Resistive electric heating only makes sense if you're looking for a low cost solution in a climate with a very minor cold season. And I highly doubt anybody's going to buy a bitcoin miner with the intent to only run it 3 weeks a year when it gets chilly outside.

Bitcoin is basically a giant scheme to extract as much value for the miners by dumping a bunch of externalities on everyone else in the form of fossil fuel subsidies and greenhouse gas production. Not a fan.

How is that different from any other of thousands of energy-intensive services?

The bitcoin network's integrity basically boils down to "Waste so much energy that a single adversary couldn't possibly waste more energy than everyone else." It then rewards individual actors for wasting more energy to make sure that stays true.

Presumably mining zinc, copper, aluminum, etc must have pretty big costs to the environment? Paper is mostly paper but isn't it also some special silk? At least here in the US.

Those seem slightly more renewable for paper. But yea, creating an extra power plants worth of fumes is pretty shitty over time.

I believe there's one currency which at the very least does some sorts of scientific calculations with the processing power? Maybe we should at least encourage those types of coins.

EDIT: Unless you live somewhere where the ambient temp goes below ~0F, get a heat pump.

But in general, I agree with you. :)

EDIT: If you're in a colder climate, in-ground coolant loops are preferred over an air transfer heat pump.