I previously considered an option that the network would be secured by competition for control (even with potential monetary losses), but was confronted with a notion that it was not economical. So I kept thinking.
There are many other ways to secure the network , like not exclusively relying on the PoW algo, but adding others which have different security considerations , benefits and weaknesses to PoW. This would make bitcoin more robust and secure. Another possibility is that nothing needs to be done because BTC grows so much that valuation alone stays ahead of disinflation or the laws of economics and thermodynamics force miners to make consumable heating devices to pay for security.(solving the centralization concerns as well)
Other possibilities of securing the network include using sidechains which perform useful tasks like folding at home, or cracking codes, selling cloud storage, ect... all give subsidies with tx fees to the mainchain which provides security to them.
Other possibilities is that volume alone can provide network security - 500k a block x 1 penny per transaction = 5k usd a block in security
We don't need to throw away our core principles so quickly without trying creative solutions to solve these problems.
I would consider the idea of network security stemming from activity and competition as the most fundamental principle of Bitcoin, which separates it from any other security models achieved by decree or elements thereof.
I agree that there are more secure models requiring less energy, but if it comes at a cost of having certain (groups of) people holding the keys, then we have stepped on a slippery slope.
In that regard being disinflationary is less fundamental than being protected by competition. But I'm not saying that we have to sacrifice the former in order to maintain the latter, just that it is the last resort option in case we couldn't come up with more creative solutions, which I'm sure we will
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