I think that you might be taking that example in bad faith.
I've got nothing against blonde dancers, and am far from politically correct myself, but in a scientific article about language and Bonobos, couldn't they have chosen a more appropriate example such as "yellow banana"?
Really seems like you're trying to enforce your own form of political correctness here - "PC" is associated with certain progressives, but the problem is policing language and picking fights over trivial nonsense.
Trust me, if you met me you would not be suggesting I am PC - but this really jumped off the page at me. Such a strange example for this context!
Think about it as a decomposition where "dancer" means "dancing person."
In the simple case, both "blonde" and "dancing" separately modify "person." If you diagram that it’s a Y: either modifier could be removed without changing the meaning of the other, and their order isn’t important.
In the complex case, "bad" modifies "dancing," which together modify "person." That’s an ordered chain, which is more complex to build and comprehend. Your clarification illustrates the chaining and why it’d be a fundamentally different meaning if that wasn’t understood.
I’m not even touching whatever you were going for with the blonde/brunette thing. It's plain they used the example because there's no possible way hair color could be a modifier for "dancing," and they wanted something unambiguous.
Never, because men's hair is "blond".
But seriously, the original quote does not call the person "a blonde," (which indeed might offend some) but instead uses "blonde" as an adjective to describe the dancer, which is perfectly acceptable. You can have a "blond man" or a "brown-haired man" just as easily as you can have a "blonde woman".