But having the VRAM allows you to run the model on the GPU at all, doesn't it? A card with 48GB can run twice as much model than a card with 24GB, even though it takes twice as long. Nobody is expecting to run twice as much model in the same time just by increasing the VRAM.

Without the extra VRAM, it takes hundreds of times divided by batch size longer due to swapping, or tens of times longer consistently if you run the rest of the model on the CPU.