You have to either physically clamp the hose, or program the car software to exclude the rear fluid spray, but that is a bit more complex. also the same hose might be connected to your rear camera's spray which you want to probably keep. I just clamped it haha, no leaks so far.
Just for aesthetics, and i don't remember the last time i used rear wipers even in the rain, so i said why not. If i sell the car i can simply assemble it back.