There's some really big innovations happening in e.g. rendering like that; I wouldn't be surprised if the complexity and work involved in just Nanite is 10x that of the whole Quake engine.
Similarly there's the work nvidia is doing, using AI technology to upscale graphics instead of rendering things at 4K.
Similarly there's the work nvidia is doing, using AI technology to upscale graphics instead of rendering things at 4K.