This is a fair point as it's not just simply using ethanol for gasoline. This article goes into more depth about it: https://www.pnas.org/doi/10.1073/pnas.2501605122
There's lot of factors at play here:
- Location for generating PV
- Redistribution of food (both for livestock and human) production
- Environmental impacts of PV vs livestock vs depletion of native prairies
Point still stands...if you replaced all of the land used to produce ethanol with PV, you would create a surplus of energy that is higher than anything we could imaginably consume today (hint - China is essentially already doing this)