You didn't say it outright so this is not me correcting you specifically, but there's this semi-myth that "Honnold doesn't feel fear because that region of his brain is smaller than everyone else's". He, at least, disputes this. He feels fear but he knows how to focus it, and it's a combination of some kind of innate talent and conditioning as he's put himself in scary situations before

Not quite the same, but Youtuber Ally Law (known for climbing cranes and tall structures) started doing it specifically because he used to be terrified of heights and now seems to not have a problem with it