Some of the largest stations by output are in northern Quebec (one of the most "middle of nowhere" regions in the world) and their power gets sold as far away as NYC.
Similarly for Chile and Argentina which have quite a few huge dams in Patagonia, which is also extremely remote.
Plus most of humanity lives within the same 100 mile range of water, esp. oceans, and the bulk of humanity live in areas with lots of sun.
Electricity acts like a medicine. What they ought to be doing is wiring transmission lines to the hydro plant to organic demand for power.
Now if the real purpose of the dam was flood control and water buffering, and the notional hydro gen facility is tertiary and irrelevant, OK fine. Mine your Bitcoin if they have all the electricity they need regionally already. But this is no proof of nothing for the crypto bros.