(The other arguments against ornamental lawns are valid. As someone allergic to many grasses, I have no love lost for lawns.)
Decades ago, I saw an article about making little basins to capture rain water in the right amount to sustain a tree in the desert to grow fruiting trees in places like the Middle East using natural rainfall in order to increase productivity of arid lands without stressing the environment. I don't believe this is standard practice anywhere in the world, much less a "developed" country like the US, but there's no reason it couldn't be a common practice someplace like California.
And those basins and other flow control techniques should be embraced ubiquitously in the west; we could green a lot up if we collaborated properly.
Politically, "they" could not and that is the problem. Think about this. Who is "they?" Who could have the political power and will to do something like that without the support of the agriculture industry?
If you're talking about actual laborers, most of them aren't even citizens and this is not a priority for them.
If you're talking about the corporate boards who run the agriculture industry, this increases cost without increasing profit so this is not a priority for them.
I just can't think of how the agriculture industry could possibly get behind this.
Something being a problem for someone doesn't mean it's a priority.
Poor people will never prioritize global warming. They will always have more urgent priorities. This is one reason why environmentalism under capitalism is absolutely doomed.
That's extremely funny. I'm dirt poor and gave up my car well over a decade ago, in part because I couldn't afford it anymore and in part because I'm an environmental studies major who takes environmental issues seriously.
I'm not rich enough to afford to smoke cocaine to fuel my delusions and then buy a compound in New Zealand and a personal jet for getting there if my greed helps rapidly burn the world down while I imagine there's someplace safe to go after all the billionaires have destroyed the world in search of their own selfish gratification.
So I make a LOT of pro environmental choices. I got no place to go and no money with which to go there.
It's also funny because it assumes the global poor are too stupid to realize that global warming means they'll become victims of war, refugees, or starve (choose one or more).
So that's one reason they can't do that.
The water "shortage" in California is an "agribusiness water shortage". Shut down a bunch of farms and California has plenty of water.