So, some engineers just stumbled upon LLMs and said, "Holy smokes, we've created something impressive, but we really can't explain how this stuff works!"
We built these things. Piece by piece. If you don't understand the state-of-the-art architectures, I don't blame you. Neither do I. It's exhausting trying to keep up. But these technologies, by and large, are understood by the engineers that created them.