It's not what I believe as I do not believe that the non-existent have the right to consent however supposing for the sake of argument they do then it is no more respectful of their consent to decide for them that they have no right to exist than it is to decide they must exist. Just as suffering is not more true or important than joy.

The reason many leftists support birth control and family planning has to do with the rights of women rather than the rights of thought experiments.