What does the 1% of land used to grow corn have to do specifically with solar and batteries? Solar doesn't need to be on the 15% arable land at all.

The corn doesn't just produce ethanol, which just utilizes the starch/sugar. The protein, fat, fiber is eaten by livestock in some form like distillers grains.

And governments like to have food security , and having secondary uses for an abundance of food in the good times is more convenient than storing cheese in caves , and in case of an emergency shortage the production is already there without having to rip up solar panels to grow food.

My conclusion is you're conflating issues (solar and ethanol) unnecessarily.