Ethanol replaced MTBE, which was good (MTBE is terrible comparitively), but now it's turned into a 43 million acre per year ag subsidy program. There is no political will to remove the subsidy, due to the folks who receive these subsidies having outsized political influence, so demand destruction will be a function of EV uptake (destroying overall blended gasoline demand over time). Agrivoltaics would also be a great alternative if you could convince enough folks to buy in.
From the last time the "ethanol is worse than gasoline" story did the rounds, I seem to remember that the entire argument boiled down to a gigantic one-time land use adjustment term that swamped the benefits. What was that about?
The fuel used for turning the soil, planting the seeds, spraying harvesting, drying. The energy used to make the fertilizer. Water and energy to irrigate. Then the refining and transportation of the alchohol.
Corn takes a lot of input energy. I believe that sugarcane is closer to break even as it requires less upkeep.
Are you thinking of the refining process?