Even that 765 is like 0.04% of the water needed to irrigate Nebraska's ethanol corn crop alone. And ethanol is basically an agricultural proof-of-work function.
You can’t eat your algorithm.
So while pointing to agriculture and saying look there - those guys & gals way more than us it’s a red herring because we need food.
Sure improve efficiency of ag, but a better comp for water usage should be made. Reasonable people tune out.
Also even in the totally fake scenario where that water completely evaporates, it's just gonna rain on Iowa a bit more.