My rebuttal is simple. If turning off half the network has next to no effect then what you did was halve your energy consumption which solves one of Bitcoins largest problems. In fact a maxi was talking about the difficulty level and the network could go down another 50% from here and still operate with almost no difference according to them.
If you halved your energy and made next to no difference to the network, why would anyone want to turn them back on and consume twice the energy for virtually zero benefit? If as you say price doesn’t follow hashrate then you don’t need the power…….
The logic of the mining network is being inside your house during the day, having plenty of natural light and then all your inside lighting turned on aswell. You Turn half the lights off and pretty much no difference but then you want to turn them all back on again.
So what is the reasoning behind wanting to consume double the energy?
Well, in theory, yes if you "turned off half the network" you would reduce energy mining energy consumption by half. Indeed, this is the exact reason why hash rate dropped when Chinese miners went off-line (although it was much less that 50% in that case). But assuming 50% cut, in such a case, half the amount of energy is then needed to create the same number of coins.
However, no one country can control mining, as a bitcoin doesn't care where its mined.
So, what of course happens in reality is that if you halve mining, yet have the same price for the asset being mined, the revenue for those remaining (or any new entrant) immediately doubles. This in turn creates an economic incentive for more energy to be devoted to mining, and hence you quickly get back to where you started. More energy, chasing the same number of new coins. (And that is EXACTLY what has happened, as the Chinese mining that went offline (dropping hashrate) was quickly replaced by new mining in the US, Mongolia, Kazakstan, etc).
Hence, if the price stays the same (let alone goes up), and you halve the number of miners, you will see hash-rate increase accordingly. Indeed, you will see this happening as fast as over the next few weeks even, as the Chinese shutdown combined with a stable price has created an incentive for new miners to enter due to the higher profit margin available.
I wonder if some of the confusion you have comes from is that hashrate is arguably an indicator of where miners think future prices will head. So, for example, say we have an existing cost neutral hash-rate, but you or me or anyone else believe that price in the future will be higher that in already "priced in" by existing miners in funding their operations. Eg lets say that consensus view is that prices will be an average of $50K for the next year, but you and I think that prices will be an average of $80K. That additional "above market consensus view" of pricing may lead us to put rigs online (increasing hash rate), with the view that we will reap the rewards of that investment in the future. But either way, again, its (obviously) ultimately the price that drives the hashrate.
Hope this makes sense!
As for the "problem" of energy consumption, its this "cost" which under the "proof of work" model, that keeps the network secure. Longer term, I believe economics will solve the problem of dirty energy consumption. Its won't be efficient, as miners inevitably move to energy that is cheapest, and essentially "free" other than the costs of construction. Think massive solar farms in deserts, hydroelectric, geothermal, etc.