Not really relevant bc it's kinda nitpicky but amazingly it's not even 4gb, it's more like 2gb if you use the float16 version (which has no quality degredations). Quite amazing that so many images fit in that small a package.
StableDiffusionPipeline.from_pretrained("CompVis/stable-diffusion-v1-4",
revision="fp16", torch_dtype=torch.float16, ...)