Yes and no. There are crops which make sense to grow in California due to the climate, which we shouldn't grow elsewhere. Alfalfa isn't one of them. We export alfalfa to other countries, essentially exporting our water. Cow feed can be better grown elsewhere (and cows can be better raised elsewhere)

Another problem crop in California is rice. We simply shouldn't grow rice in this state. Most rice is grown in the southern US where water is plentiful. We could stop growing rice without significant impact. More water is used in California growing rice than all of Los Angeles residential use put together.

We could cut these crops significantly without appreciable impact to our food supply, using a fraction of our existing conservation budgets, and not have to worry about residential conservation for decades or longer.

There's a pretty good intro to the economic breakdown here: https://slatestarcodex.com/2015/05/11/california-water-you-d...

In states with a more reasonable water usage?

California is the #1 agriculture state in the US by dollar amount (most is dairy, almonds, and grapes/wine).

Pretty much anywhere else with sunlight, soil and water?