> It's also very possible that transactions fees alone actually will be sufficient to support a high enough amount of hash power to secure the network.

I have to admit that I have no idea how much work is actually needed to secure the network. My point of view is that the current rate of energy expenditure outweighs whatever benefit Bitcoin does or could provide to society. But if this rate is a transient result of still-significant minting going on, things could definitely look different in the future.

Do you know of any analyses on how much work really has to be continuously expended in order for Bitcoin to remain reasonably secure at a given market capitalization?

I don't see why many nations would jump at the opportunity to make Bitcoin their monetary backbone. For example because an immutable monetary policy won't be seen as a feature.

Bitcoin proof-of-work difficulty must always increase, the electrical needs are always ever-growing. While you claim that incentivizing electrical production is what POW does, in reality it is a large drain of electricity on a finite electrical grids capacity and it DOES take away from other uses of electricity LIKE aluminum smelting or running hospitals. It is an active and actual source of pollution and uses more electricity than most countries. You can’t handwave this away or insist upon your rhetorical framework when. The apparent physical real world consequences of POW cryptocurrency cannot be evaded or ignored.

I don't see how cheaper energy would help. Bitcoin needs a certain amount of power in units of cost to be tied up mining to secure the network. If the cost of energy goes down ten times then the same PoW requires ten times the energy.

“as mining is more economical”

Mining doesn’t use a fixed amount of energy. As it becomes more economical more people will mine.

I agree with this. Just want to add, bitcoin mining can happen in remote locations with available power (hydro, geothermal) which are too far from cities to be transported by power wires. There is a limit to how far you can transmit electricity through wires. So, there are tons of untapped natural energy sources.