For general power delivery to the grid I think renewables make a whole lot of sense. But for specialty industrial processes that require very large levels of constant power, I think nuclear fusion is very interesting. I worry about environmental effects of mass industrialization but at the same time, I wonder what we could achieve if we had 100x more power available for this or that industrial process. Would it be helpful in decarbonizing steel refining or other metallurgical work?
I think if we develop the technology we will find a use for it and be grateful that we have it, even if it’s hard to predict today what those uses will be.
I am excited for how much bitcoin we could mine if we had a dedicated nuclear fusion plant.
If you mean "we" as in "humanity", then exactly the same amount. Bitcoin is created per unit time, not per unit energy.