Chemotherapy is the known cure for cancer, so a more accurate statement would be saying, "Pain killers are pointless, just find a cure for the cancer." But no

Chemotherapy is the known cure for cancer, so a more accurate statement would be saying, "Pain killers are pointless, just find a cure for the cancer." But no one is saying painkillers is pointless. Parent is saying painkillers should be temporary. I suspect they forgot to mention the "in an ideal world" bit.