No no, it's entirely dependent on the lighting, how complex the geometry is for all of the characters, props, and terrain is, and material settings. In this case, the backdrop of the stage is very real (and a lot of the props back there are quite reflective), creating more complex light bounces, which in turn created more noise. If you just have a light or two in open space with simple materials, then you could probably get away with 128 samples, or even less.