It's common practice for TV directors when working with only one handheld camera to shoot the interviewee's face from over the shoulder of the interviewer, so that viewers only see the side of the interviewer's face. (We were teaching kids that, in the school's TV studio, back in the 1970s and '80s. It avoids the camera swinging backwards and forwards between the two participants, which looks amateurish and can even induce a sense of motion sickness in viewers). You'll normally only see the interviewer's face when a second camera is used, enabling the director to cut between the two.
So my guess is that Games' organisers have either restricted the BBC to a single poolside camera or simply that the director has chosen to allocate his/her resources that way.