You can’t glean insight about evolution from this. Hunger doesn’t follow a steady rate of making you irrational or whatever else. People who are used to it can go 18 hours without eating just fine. In fact they might report that it makes them sharper. While other people get “hangry” if they don’t eat every four hours.
This is a fair point about different conditioning to hunger, which to some extent, we are all capable of attaining. Those responses you mention do seem like evolutionary adaptations themselves, which may nevertheless vary across individuals. Such as ketolysis making people sharper mentally, which I've certainly experienced.
Your point about that making it hard to tell what evolution may have wanted from this, given such variety, is fair. However it's not necessarily a point against an evolutionary trend here, just because responses are varied. There could be adaptiveness, in aggregate (as it always is in these considerations I think), to having some people express different responses.
I think this stressor is ripe for gleaning insight about evolution, tho. Because of how critical food is. And therefore how much effective ways to overcome food loss would have been critical for evolution to hack at. It's likely evolution has laid out a series of algorithms for us, depending on what stage of hunger we are at - each developed to be the most effective balance at that stage between resource usage, and search success.
In that sense the different modes you describe "hangry" and "hunglightened" (and possibly some more in between) are most likely evolutionarily designed "behavior algorithms" that each maximize adaptiveness for finding food and surviving at each stage of progression towards starvation.
I really think you should think more about it, because how could it be any other way? Food is so crucial, evo is obviously going to get right into how we react to its absence.
Of course if your point is more about difficulty in concluding from the paucity of data in this discussion, I'm all with you! We are just hypothesising now, which is perfectly valid. And, for me at least, insightful. I feel truly sorry for you, that you didn't find it that! :)
I'd like to end with this weird little side-note counter: another pithy aphorism about food and performance: never make any big decision on an empty stomach! Hahaha! :) Many have said that.
