Big farmland is effectively dead. It must be tiled and heavily fertilized to produce anything. It does NOT have healthy soils.

And remember the context: were talking of replacing corn grown for energy, monoculture with no insect or plant life, with the same land covered with solar panels, time for soil to recover, native plants to germinate and grow.

Putting solar panels instead of the industrial corn production is partially rewilding it - there are projects in the hotter countries where increased humidity and decreased sunlight actually allows for the more plants to thrive. There are projects using goats to trim the greens under the panels. Etc, etc.

Almost anything is better for the soil, biodiversity and life than industrial corn production.