It doesn’t matter if farmers get the subsidy. The subsidy increases demand artifially driving up prices.
I would say the mandates go farther for creating demand than the subsidy. A 45 cent subsidy doesn’t have the punch it used to when gasoline was less than $1 per gallon when the subsidy was created.
Bottom line is this - ethanol won’t be around forever. What you will see is either something like butanol or an ester fuel ultimately made, with the protein, oil, and valuable pharma and nutraceuticals extracted up front, with a near 100% carb composed of relatively simple sugars in the fermenters.
What I can tell you is that the days of cheap, subsidized meat (the original ethanol) and grain going overseas on barges is over. The farmer isn’t going to take it in the shorts anymore to kowtow to govt policy goals.