For example, someone who was completely colorblind from birth could never understand what it felt like to see the color green, no matter how much neuroscience that person knew, i.e., you could never convey the sensation of "green" through a layout of a connectome or listing wavelengths of light.

The 'colorblind-synesthete'?

Also see orthonormal's posts here (and accompanying discussion). I remember the point being similar to "I might know all about heroin and how I'd respond to it, but taking heroin means that certain neurons release chemicals in ways that I don't have conscious control over, and it e.g. will cause memories to be formed that I could not form normally."

The real question is how mechanistic matter can create subjective experience.

Philosophy (which today is mostly a historical field - the study of old speculations) is not the right place to find the answer to this question. Computational neuroscience is.

Rather, it only poses problems for those who say that brain states are the same thing as conscious experience.

The 'problem' is overstated - the mindstate of observing green through information flowing from the retina through multiple layers of visual cortical processing is in a wholly different category than the congenital colorblind's mindstate of thinking about green as an abstract linguistic concept.

The two mindstates are completely different and involve largely unrelated computations in functionally distinct minds.