That appears to be correct. The MB229.5 oil spec for the 2.0L lists those oil viscosities vs. the anticipated temperature ranges in that diagram. However, if you look carefully at the VR30 section of the Engine Oil and Oil Filter Recommendation section of the Owner's Manual, you'll see it's worded identically to the 2.0L section. So the viscosity recommendation to select the appropriate engine oil viscosity based on the temperatures the engine will be operated in before the next oil change still applies.If you look carefully in the Owner's Manual, that 'Outside Temp Range' diagram (JVT0428X) is under the 2.0L section. It is not present under the VR30DDTT section.
While there are more acceptable oil viscosity choices for the 2.0L engine, Infiniti still offers a limited choice for the VR30 engine based on anticipated temperatures before the next oil change.
From the Service Manual:
So the way I interpret this is as long as the oil meets API certification, you can use either 0W-20 or 5W-30 engine oil in the VR30, depending on your anticipated temperature range before the next oil change.