For non-gaming tasks you can get by with a lot less memory. The ONLY theoretical place this might benefit is if video editing programs could properly populate the VRAM and take advantage of it but that's not the case.
I can't think of ANY scenario that more than 2GB makes practical sense for this GPU.
*To be clear, you can increase resolution, anti-aliasing etc for a game to drive up VRAM usage but then that drops the FRAME RATE so low as to be unplayable. That's why there's a relationship between VRAM and GPU performance.