10,000 hours is for expertise. While expertise is nice, any given individual has limited time and has to make some decisions about what they want to be an expert in. Claiming that everyone (or even everyone who wants to figure out what's true) ought to be an expert in rationality seems to be in conflict with some of what Luke says in chapters 2 and 3, particularly:

I know some people who would be more likely to achieve their goals if they spent less time studying rationality and more time, say, developing their social skills.