This is the same shot three times shot with camera with different amounts of dynamic range:

Often high dynamic range is sought after as the dynamic range of the eye is very high and as such high dynamic range of the image makes it feel pleasing and natural.

It is important to understand though that if you know how to utilise the dynamic range of the camera you may not need the high dynamic range.

These images are shot on cameras with different dynamic range, but in my opinion the final image with the lower dynamic range doesn’t suffer because the camera is exposed well for the scene. Often times good technique and understanding of the tools helps more than gear.

The Blackmagic Pocket Cinema Camera 4K is tested to have 11.6 stops of dynamic range at a signal-to-noise ratio of 2 by CineD.

The Arri Amira should have the same Dynamic Range as the Alexa Classic as they use the same sensor and the ALEXA Classic has been tested to have 13.8 stops at a signal to noise ratio of 2 by CineD

Signal-to-noise ratio is used to express how much signal (image) there is compared to the amount of inherent sensor noise. A signal to noise ratio of 2 is usually a pretty baseline to measure from.

When is wide dynamic range good?

A camera with wide dynamic range is often preferred in modern filmmaking as it allows for a more (traditionally) pleasing-looking or natural-looking image. This is because the dynamic range of the human eye is very wide. Many modern cameras perform really well with regard to dynamic range.

When shooting outdoor scenes where there may be limited control it is often desirable to have a high dynamic range because the scene often contains a very high difference in its brightest and darkest areas.

In a more controlled environment, dynamic range may be less critical because we can light the scene within the dynamic range of the camera. Nevertheless, wide dynamic range can still provide benefit to preserve bright practicals for example.