I wouldn't be too worried about it (that is, about being forced into buying it, not about using it; Ethanol sucks, period).
For one thing, many states force or limit the amount of ethanol in fuel.
Around here it's E10, or nothing (E85 is allowed, but that's a different story).
But the big reason this isn't a concern is more about logistics.
The infrastructure of gas stations limits what they can sell.
At one time, stations had tanks for regular, super, midgrade, diesel, etc., and each pump, pumped from each tank.
Nowadays, most stations have tanks for regular and super, and the pumps blend the fuel into the octane that the customer selected.
Still, all of those fuels are pre-blended with ethanol, so in order to sell E15, they would either have to give up selling E10, (and gas stations aren't going to stop selling to cars from 2000 or older; that's probably a quarter of their sales), or install several new tanks and pumping islands (i.e. tear the place down and rebuild) before they could sell both.
I suppose there might be a day where ethanol is blended right at the pump, but if stations ever get that capability, they would probably have a button to let you buy E10, E15, E85, or even E0 (except around here, where E0 is not allowed by law), so I don't see how we would be forced into buying E15, but I agree with you, in that the less ethanol, the better.