Because of this drawback, LLMs are actually a decent model for this sort of process since we can observe how they operate. I'm not claiming they're actually intelligent like we are, but rather that they model the process of drawing connections and making associations close enough to how we think to the point where it's an useful analogy.
Maybe the entire process isn't like feeding an LLM, but that step is. Relevance identification is an interesting part of the process. The LLM can do a decent job of making connections, but it doesn't know what is relevant. In the longer time frame of the thinking process, we constantly throw out data as irrelevant or identify previously unknown relevant data that needs to be added. It's a part of the process completely outside of the LLM.