The bell curve meme is a static taxonomy of people, and if the link you posted is correct, its origins were explicitly political. The version described by Bruce Lee, and anybody who has achieved a high level of skill, is about the process of learning and mastery.
In the bell curve version, the wisdom of grug brain and the wisdom of the monk are presented as equal, and the struggle of the midwit is framed as a pretentious, unnecessary aberration. The lesson it teaches is, don't seek out knowledge and new ideas. Education confuses the "midwit" people who are smart enough to partially grasp it but not smart enough to see through it like the monk.
In contrast, the "a punch is just a punch" version frames the conceptual struggle as a necessary phase in a process that leads to mastery. The beginner cannot engage directly with the simplicity of the master, so the beginner must engage through concepts and through practice. The more they do so, the more simple things begin to feel.
Since this started with a Bruce Lee quote, we can use him to see that it is not just a linear process that passes through conceptual education and ends in mastery. That leads to a dead end, because mastery can only be complete in a limited context. Bruce Lee kept searching outside his zone of mastery to find ways to get better. He studied techniques from other martial arts and fighting sports, even though in doing so he had to engage at a conceptual level since he had not mastered those arts.
For example, his art included trips and throws, and he was a master of his art. Yet when he got the chance later, he practiced judo with expert judoka. To do so, he had to back off from "a trip is just a trip, a throw is just a throw" and learn the techniques of judo. I don't think anybody has ever suggested he was a master at judo, which suggests he had to be engaging with it on a conceptual level. Yet he believed that his practice with judo improved the skills he had already achieved mastery at.
Not only did Bruce Lee preach constant assimilation of new ideas, he also preached simplification by discarding what is not useful. If a punch is just a punch, what do you discard? The whole punch? In order to find something to discard, you must look past the apparent simplicity of the internalized skill and dissect it conceptually.
In this view of things, conceptual thinking is not just a phase you go through on the way to mastery, but rather a complementary way of engaging with a skill. It is a tool for refining and elevating your intuitive mastery. Simplification and desimplification are the tick-tock of learning. A "mastered" skill is not like a video game sword that, once forged, always has the exact same stats, but is more like a Formula 1 car that is continually disassembled, analyzed, and rebuilt.
The bell curve meme does occasionally get used to express a linear ignorance-struggle-mastery story of learning, but its origin and most common use is to caricature the pursuit of knowledge as pretentious foolishness.