This idea/delusion that energy that is used for mining should and could have been used for something else. It's just not the case.
It’s pretty clear the GP means a demand curve: cryptocurrencies induce demand for energy sources that would otherwise be uneconomical to operate. This doesn’t require fungibility.
Okay, but the 'if' there is true. Bitcoin is currently inducing demand for coal and gas plants, which is very bad. It's unclear when it'll stop doing that, if it'll stop, and a hypothetical future in which Bitcoin starts incentivizing the good thing instead of the bad thing doesn't change the truth value of the current bad thing.
(We've also fixated on coal burning, when there are oodles of other great reasons to not like Bitcoin. A small handful of them have been listed elsewhere in this thread.)
If somebody proposed a law tomorrow that bans coal plants being reopened to mine Bitcoin I wouldn't be against it, and Bitcoin would carry on happily regardless.
BUt you're then getting into the dangerous territory of telling people what and what isn't an acceptable use of compute power. Bitcoin is a valid and useful consumer of energy.
If Bitcoin is neutral as you say, it cannot incentivize renewable production. It can only induce energy demand and, consequently, seek out the cheapest energy on the market. It doesn't get to sit on any laurels for that, any more than car manufacturing or aluminum refinement would. Except, of course, that those actually produce things.
If we had abundant clean energy everywhere with no unclean power plants, then knock yourself dead. But right now, any power consumed has an unclean component.
Even if you use power in a country that is 100% renewable, it takes away power from a grid that is then replaced by non-renewable energy. And that these miners buy old crap power plants make it worse - it reverses grid-wide improvements to green energy.
... heck even with fully renewable energy for the entire globe, wastefully burning energy so that more renewable power sources need to be deployed is still bad - no power plant is neutral to manufacture.
And re: comparison to call of duty, if had the same footprint as Bitcoin, then we could start talking. Bitcoin consumes power like a small country, not like someone forgetting to turn off the lights. All for something that can be done without any of this power draw.