The visual style of this short is very unique, vibrant, and expressive. And the stop motion here is just the plump, colorful, and juicy cherry on top.
But war is hell. "Neighbours" does an incredible job of showing how, and it does it sporting the core message, "Love your neighbor, meaning, to treat others as you would have them treat you." This short wasn't made too long after the Second World War, and it's apparent just how lingering of an effect the war had on the world, and the art that was produced at the time.
Basically, I'd classify this as something of an essential view. It's unique, it's unconventional, it's well-made, it's got a great message, and most importantly, it's got grown men kicking babies.