Can’t Decide On Genocide

(A friend and I are talking arguing about which side to support in a dispute in a game he plays. One side is trying to cure a disease that turns those it infects monsters, but it does allow them to retain some intelligence, as they are a hive-mind. The other is just focused on killing them. I support the former, my friend the latter.)

Friend: “But why would you want to cure them if you can just kill them all?”

Me: “[Friend]! That’s genocide!”

Friend: “It can’t be genocide if they’re not people.”

Me: *speechless*