And yet I am of 100% precisely the opposite mind, and don't understand where you're coming from with this notion.
People don't act like perfect logic-engines that dispassionately analyze things and then pursue the calculated most logical course. Yes, people do try to act rationally, but "trying to act rationally" simply does not mean "exclusively perfectly rational and pragmatic decisions". Sometimes, it's because they lack critical information (whether through inattention, others' deception, jumping to conclusions, whatever). Sometimes, it's because "their set of values" precludes perfect rationality and pragmatism. Sometimes, even when they know what is rational and their values-system doesn't preclude it, their emotional response is more relevant.
"Rational fiction" is almost always a load of hot garbage because it spends half the word count of a text belaboring the point of how perfectly rational the people in it are behaving. Yes, we should expect people to exhibit some degree of thinking about what they want, and to try to pursue that in ways they believe (rightly or wrongly) will be effective. But that's a FAR cry from people being "perfectly rational and pragmatic". Almost entirely the opposite, actually. People act on intuition. They dismiss information that's actually important but they believe it isn't--not because of their "set of values", but because they're distracted, or prideful, or deceived, or...(etc.)
Note what the person you quoted described: "It's hard to create an interesting story around a character who always makes the most rational, pragmatic decision possible." Meaning, not just within a values-system, not just within the personal quirks and foibles of the character, etc.--THE MOST rational, pragmatic decision possible. Perfect optimization.
Perfectly optimized decision-making machines aren't particularly interesting to follow, outside of rare circumstances. Even Sherlock Holmes, notorious for his logical-pragmatic nature to the point that nowadays the default presentation is "on the autism spectrum" (with a frustratingly common side of "...and an absolute jerk to everyone else", even though that directly contradicts his behavior in several of the stories), isn't like that. He makes foolish decisions. He gets deceived and manipulated. Yes, he's trying to solve his cases. But "trying to solve his cases" doesn't mean he always makes the most rational, pragmatic decision possible. Often, he falls short of maximal rationality and pragmatism.