It wouldn't be murder, it would be... I don't know... enhanced natural selection? Self selective attrition? Idiocy inspired abortion? It's literally the outcome when you say "If all your friends jump off a bridge, would you do it?" and the asshole starts screaming yes at the top of their lungs.
When you are literally lightyears beyond the point of common sense being common, and reason is long gone, and every thing the "other" does is to show you up for no other reason than they can: They're going to start killing themselves anyway, might as well coopt the process and push it towards efficiency.