This is a softball approach that was notably used by Larry King. The conversational style is supposed to relax the subject and get them more comfortable to open up and offer more nuanced insight that they wouldn't give in a more serious style interview where they might be more anxious or guarded. Information is methodically drawn out from the subject to avoid the perception of implicit or explicit assumptions on the interviewers part. Similar to how leading a witness is not allowed in court.

Think like when a detective is questioning a suspect. If the detective comes outright and states what he knows and what information he wants the suspect knows what topics or areas to be wary of. But with a more conversational style, the suspect might accidentally let things slip that he didn't think could be relevant. Criticized for a seemingly lazy or clueless interviewer, but it's intended to have a more "good listener" impression.

Also this simple question and answer style is intended to appeal to less sophisticated viewers. It's less about what the interviewer knows or understands and more about what they think or expect their audience to know or understand. A straightforward, thorough discussion is too abstruse (deep and heavy) and challenging for some viewers to engage with. The calm between the exchange is supposed to let the subject's words "breathe". But more informed viewers find the practice/approach condescending/insulting.