meh
Much of California has an excellent climate, (when it rains), to grow a number of popular crops. If much of the California agriculture that requires more than available water were to fail, consumers would either switch to the same crops imported from Mexico or Peru (as they do, now), at somewhat higher prices, or they would switch back to the crops that were available before refrigeration and artificially depressed water costs created the current California agriculture.
However, even the current drought is only a heads up warning for the eventual collapse of most California agriculture. Unlike the regions east of the Rockies and north of the Red River that are primarily supported by rainfall, California has always been reliant on irrigation. Irrigation has a long and notorious record of destroying the soil in which it is employed due to mineral deposits, primarily salt and selenium. Mesopotamia, Western Levant, and Egypt were the cradles of civilization because irrigation allowed agriculture to develop. Much of that “fertile” crescent is now the deserts that appear on the nightly news. (Irrigation continues to support agriculture in a reduced region nearest the rivers, but there have been a number of periods where civil disruption interrupted the irrigation and allowed the lands harmed by salinization to recover. It is likely that salinization utterly destroyed Sumeria and the salt swamps at the southern end of Mesopotamia still do not support crops.) Unless we are planning to abandon agriculture in the Central, Imperial, and San Joaquin Valleys for a few decades, (or science comes up with a miraculous solution), California’s current crop load is heading toward a crash. This will not occur in the next couple of years, (unless the drought exacerbates it), but it is already a source of concern.