After having pondered this thread, I can easily say that Dynamic Range is not important, unless it is. All else equal, I will take more DR than not.
There are many images to be made that easily fit in the DR of almost any modern camera. And when the important areas fall to one end or the other, blowing the highlights or blocking up the shadows is a good trade off. However, when important aspects fall at both extremes, then there are issues. Classic example being sunrise/sunset images or inside/outside images like that posted where important details exist in both areas. In fact, excluding the garish (or artistic) over saturation of some HDR images, we often think they look unnatural because for so long we were used to blowing out the top end or silhouetting something against the bright sky. To be able to preserve detail in both violates our traditional expectations, not necessarily the real world or eye's ability to adjust to it.
Having additional 'headroom' though is always a benefit. It makes pushing and pulling the data around in post processing easier and allows for ETTR when clean shadow areas are desired. And if we are talking about our ability to composite multiple exposures, that is a 'hack' that is very useful, but also has limitations, especially with dynamic subjects and lighting.
Finally, it is impossible to to judge DR and quality of the RAW data from 2 cameras based on RAW conversion because of the unknown assumptions built into the conversion engines and our lack of confidence that the propriety file was correctly decoded as intended by the manufacturer. Take the same raw image and decode in multiple engines and while you can get close, very rarely can you get to the point of eliminating visual differences, let alone be able to duplicate the numerical results. But at the end of the day, a photographer will have a set of tools and set of skills which may be better suited to a particular type of image or images from a particular camera than some other types of images or other cameras. Of course, this precisely why the user community would prefer a well documented standard RAW file than the camera maker proprietary ones.