Have you seen the logistics required to move the output of 15,000 acres of food to the consumer?

A 15,000 acre solar farm generates 6000GWh a year, which can be moved via a single high voltage pylon.

Of course you don't need to move it to California, as you can power an Iowa data centre, or Chicago, instead.

People may pay more to ship "Florida Oranges" or "California wine" across the country. They won't with electric, they'll just buy locally, and if prices reduce then people will use more (building new data centres is the current vogue, but factories and other industry)

Iowa being a net energy exporter means more economic opportunities for Iowa

The Eastern and Western grids are interconnected.

Energy can't be moved as easily as food

It can be moved much easier. Electricity moves at the speed of light (through an ideal conductor).

If you generate electricity in Iowa you can't easily sell it to California.

Within the Eastern and Western grids, power generated anywhere can be easily sold anywhere else within the respective grids. For example, the Intermountain Power Project in Utah has historically supplied a significant portion of electricity to Southern California.

Moving power between these grids is a little more complicated --- only because the grids are not synchronized. But this too is technically possible and could be made easier if there was more demand to do so.