Most modern cars can (or could if the manufacturer would have put in the effort) be made to run *better* on ethanol than on gasoline. While the ethanol production methods aren't really viable and older cars have serious trouble with ethanol because their fuel system simply disintegrates, in any car you buy new, you get more power and a cleaner burn from the E10 than from "premium" or "regular" classic fuel.
I agree that it would be good for owners of older cars to have the option to buy "pure" fuel so they don't have to deal with fuel hoses and pumps breaking on them. I agree that the current production methods don't actually make E10 a competitive fuel since they need government subsidies to make them affordable. However, I don't agree that E10 isn't "the good stuff" for most cars on the road, if you purely look at what your car runs best on.