Ethanol will destroy engines that are not designed or modified to burn it. E10 was bad enough, but E15 will damage a lot of engines in the near future.
IIRC using gas with ethanol in it was considered to be more harmful to small engines found in motorcycles, lawnmowers, etc. than larger car and truck engines. The libs hate things such as mowers, leaf blowers, ATV’s, motorcycles even more than cars in many cases.