If by banned, you mean to children?
I am not a lawyer, but I believe it falls under endangering the welfare of a minor, lewd and indecent conduct etc. and certain legal thresholds have to be met. Again, not being a lawyer, your child walks in on you in the bathroom will probably not get you sent up the river (although the zero tolerance nazis would probably love to) but sitting down to an after dinner sex video would.
And I don't know why this is the next next topic.....because porn is not outright banned. Grossman is calling for FPS games to be outright banned at least that's what I am getting from his remarks.
I don’t think he wants a total ban; he wants very severe restrictions, and to ban kids from accessing them.