I think Lex is prepping his interviews very well. He will ask questions that address the areas in which the interviewee is an expert in. However, you begin to realize that he often struggles to ask follow-up questions that are relevant to what the interviewee has shared on various topics.
This differs in other podcasts. For example, Sean Carroll, a theoretical physicist, conducts interviews with colleagues, who are also theoretical physicists. This enables him to engage in a meaningful conversation with the person being interviewed. When both parties strive to use language that a wider audience can understand, it truly becomes enjoyable.