I don't think that nordic customers make up that many in the J cabin going to Asia. There are many connecting from western european countries and many Asians going the other way (the majority in my opinion when you look at the passengers waiting for an AY flight to Tokyo).
As for J cabins being nice when travelling with infants - that's another tiny proportion of passengers and no doubt everyone else in the cabin would prefer the kids left on the other side of the curtain.