Ultimately any two ambitions will compete with each other for finite time and energy. (Assuming each ambition benefits from more time and energy being spent on it, which is usually the case.)
You can be reasonably successful in multiple areas, but you can't max them all, you have to compromise somehow.
I read the post as the author acknowledging the compromise, expressing frustration about it, and determining to live on the pareto frontier with his strategy of focus and discipline and so on. Sacrificing other things in order to achieve both ambitions at a high level (though not maximizing either one).
You can be reasonably successful in multiple areas, but you can't max them all, you have to compromise somehow.