It's a slightly higher-flown version of "We can't talk about your problems because other people have worse problems!"

The problem with that idea, in addition to it being morally repugnant and utterly disdainful of human life, is that there's always a worse problem. Oh, you want to talk about polio? Malaria is a worse problem! Oh, you want to talk about income inequality? Access to abortion is a worse problem by far!

It's a perfect way to shut down any discussion, simply by shouting "HEY, LOOK OVER THERE! WORSE PROBLEMS!" and claiming the moral high ground.