think of rationality of the brain like a signed vs unsigned char in most implementations of C, basically a byte: you could think of a byte as 0-255 or as -127 to +126. The brain is an emotional organ. Rationality is the best possible outcome, but it's not the default state; the brain doesn't function from 0 to 255 rationality, it functions from -127 to +128.
I say it this way because you talk about rationality "breaking down" as if it's some sort of default. I don't think of it that way. Rationality is something we hope to build up to and are lucky to achieve, but our default state is animal passion.
I'm not trying to convince you to change what you think, just using some restatements to open your thinking to the way psychiatry views the brain.
I'm sorry, can you please explain how you come to this conclusion based on what I wrote:
"however the part of it that has "rational debates" is not an intrinsic behavior. that part is based on cognitive skill which will perform to a greater or lesser extent based on current brain state."
I'm not really arguing with you, as your first point seemed to be some kind of "but what about...!" that didn't really negate what I was trying to say. However if you think I was saying something completely different, that would make more sense for whatever it is you're attempting to "argue".
This has significance, it's not just a restatement of "the problem" using different terminology. It's significant because the brain, like every other part of the body, evolved parsimoniously, and it does not have spare capacity lying around, so anything that "distracts" the emotional parts of the brain will diminish rational capacity. "Hangry" is not just a pun/quip about being hungry, it's empirically measurable, it affects outcomes.
Debating rational topics with your rational friends, whether at work, at school, or after hours over a beer, it's fun (emotion), can be frustrating (emotion) but does it ever not get heated (more emotion)?
The brain is an emotional organ. All the other organs are rational, they do what they do in entirely predictable and logical ways.