The rationalist community doesn't focus strictly on epistemology (though it is a big focus). They often bring other areas of the humanities into it too, like moral philosophy (like your food production example). In any case the situation is the same. They think they are the first to consider these questions, and are completely oblivious to the vast academic research that has been written on the topic. So they reinvent the wheel and collectively make a lot of beginner mistakes without realizing it. Then they write blog posts that flesh out these poorly informed and poorly reasoned ideas, and act like these blog posts are major breakthroughs in human thought, when they aren't. They only advertise the ignorance of the community.