..Nikon increases preservation of shadow detail more than highlights, Canon increases preservation of highlights more than shadows. Again, which is 'better' depends on the photographer. Me personally, when a scene captures my eye and makes me reach for my camera it is specifically the interaction of light and shadow that made it appealing. I am not concerned with nor desire to process out all the shadows, that would completely ruin the imagery of the scene/subject. If I am concerned about anything it is highlights being blown out when wanting to maintain shadows being shadows.. I mean I want the shadows to be just that, shadows. If I could not make out what was in the shadows at the moment of capture, I have no concern with seeing it in the image.
Dealing with the ends
of a system's DR can be both relative and subjective as far as this kind of image interpretation goes.
But what about when some bodies (coff coff 5D2 coff) actually generate visible pattern noise in midtones (like blue sky) or darker areas that are not even in pushed shadows?
Also, as part of an artist's interpretation, simple controls like contrast and brightness, even when used sparingly with a camera's built in scene mode or picture style, can sometimes bring out these patterned noise artifacts. so it's not always heavy post-processing required to show some of these problems from some bodies. Some low iso images have problems right out of the camera and same with some hi-ISO blotchiness.
I don't agree with your opinion on noise processing.
Patterned noise is nearly impossible to get rid of, uniform noise is easier to remove or can even be left in as it's less obtrusive than patterned noise.
No comparison in lenses. Canon offers a greater selection in their 'pro' lenses than Nikon. Canon offers users the ability to get into pro glass without having to buy the ONLY and most expensive lenses they make like Nikon does. For example (and there are many) the venerable 70-200mm lens you will likely find in any pro's bag, and one most everyone else wants at some point, Canon provides four options from ~$600 to ~$2400, all exceptional optic quality - Nikon has ONE and fork over ~$2400 for it or do not even think about a 70-200m..
That is only one example, but a good one. You still have the option of choosing and using 70-200mm class lenses they've made over the past 30+ years tho. So there's a price point for everyone if you don't mind using some older, possibly manual gear. Not that different after all.
OTOH, Nikon has some great lenses Canon doesn't, like the UWA benchmark 14-24mm.