For years, my standard response to “right-to-die” arguments, is to ask when it will become the “duty-to-die”. Usually the death cultists obfuscate, and avoid that question — Tutu has laid it on the line.
I use a similar argument on the "too many people" people. I ask them, if they think there are too many people on the planet, why are they still here? Then I call them on it, stating it's very liberal of them expecting others to die for their purpose.