I tried typing those queries (and related ones) into google, to see if someone could easily find some sort of starting point for rationality. "How to think better" yields many lists of tips that are mediocre at best (things like: exercise, become more curious, etc). About halfway down the page, interestingly, is a post on CSA, but it's not a great one. It seems to mostly say that to get better at thinking you first have to realize that you are not naturally a fantastic thinker. This is true, but it's not something that points the way forward towards bayesian rationality. (by the way, "how to figure out what's true" provides essentially nothing of value, at least on the first page).

In order for someone to go down the path you've identified on their own, as a curious individual, they would have to have a substantial amount of luck to get started. Either they would have to have somehow stumbled upon enough of an explanation of heuristics and biases that they realized the importance of them (which is a combination of two fairly unlikely events), or they would have to be studying those subjects for some reason other than their instrumental value. Someone who started off curiously studying AI would have a much better chance at finding this path, for this reason. AI researchers in this instance, have a tremendous advantage when it comes to rationality over researchers in the hard sciences, engineers, etc.