My personal experience is that I had most of what enables me to be epistemically rational from childhood (so probably genetic), but that the exposure to behavioral economics, science and other rationality-adjacent memes early in my life significantly boosted that genetic seed.
Another personal observation: I have never felt someone I know has improved their rationality. Though I also don’t know almost anyone who even cares about becoming more rational.
My personal experience is that I had most of what enables me to be epistemically rational from childhood (so probably genetic), but that the exposure to behavioral economics, science and other rationality-adjacent memes early in my life significantly boosted that genetic seed. Another personal observation: I have never felt someone I know has improved their rationality. Though I also don’t know almost anyone who even cares about becoming more rational.