That potentially just shifts to another zero sum game for water rights. The West is dealing with that currently.
There are residential and agricultural technologies that dramatically reduce water usage. For instance drip irrigation. Also the city of Las Vegas recycles almost all the recyclable water and consequently is extremely efficient at using water
I’d worry that it would upend agrarian economies (in the short and medium term, at least $
That just pushes it to another zero sum game of money.
My point is that in a world of finite resources, it's going to be zero-sum at some point whether that's land, water, money, labor, or something else. It's not good or bad, but you do have to pick your poison to a certain extent.