Bit depth is about dynamic range, not the number of colors

The above is the title of an article over at DP Review which can be found here:
https://www.dpreview.com/articles/46534 ... to-capture 
I read through the article and all the comments and wonder what your take on the subject is?. Agree, disagree or stand somewhere in between. I must admit that some of the discussion I didn't understand - references outside my sphere of understanding. Since the author challenges the established norm, I'd like to hear your thoughts - is he right or wrong? 

The article is correct - it really isn't a debate, just a misunderstanding by many photographers, especially those that aren't highly technically inclined.  But don't apply that to the difference between 8 bit and 16 bit color files.  Virtually every camera on the market in the last 10 years has more dynamic range than 8 stops so it does matter quite a bit and there is a huge visual difference between 256 shades of gray and 4096 or any color for that matter.  But in the case of 12 bit to 14 bit, it matters if the noise floor of your camera is low enough as described in the article.  Similarly, some medium format cameras record 16 bit color but even the very best of them can only record 15 stops of dynamic range and that is in mathematical models.  So even on a $50K digital back, one of those bits is wasted and in real world photography terms, it's more like 2 wasted bits.

But, now lets step into the theoretical world of zero noise, then bit depth becomes purely about the number of colors per channel that can be recorded.  It's just that in the real world, the bottom bits are below the noise floor so those colors can't be realized.

On a related note, the best site to compare real world dynamic range vs ISO and vs other cameras is the following:
http://www.photonstophotos.net/Charts/PDR.htm

Thanks E.J. you explained more clearly than most of the comments.