I'm not sure either. "Culturally imposed" doesn't mean a lot to me, either. A great deal is "culturally imposed" on us. Speed limits are culturally imposed. So are clothes. If he means he wants to end discrimination based on prejudices, then I'm on the bus with him. However, other than the requirement that sperm donors be male, I'm not sure what "cultural impositions" there really even are, anymore. Personally, I don't think ending discrimination has to mean ending the enjoyable experience of sexual differences.