And the answer seems obvious. Yes of course you should do your best to establish a good rapport. If you are working all day with someone it is important that you get on well together.
One of my favourite clients, an international HR director has excellent interpersonal skills, is very friendly, charming, empathetic and makes candidates really feel welcome and at ease. And most often when he is assessing candidates commonly his verdict is ’too relaxed, not dynamic, did not focus enough on the job tasks’. The candidate made the classic mistake of empathising with the interviewer’s informal style rather than the role.
Interviewers are not looking for a friend, or someone they feel they have a lot in common with socially. They are interviewing you with the sole objective to fill a role which requires a range of technical and particular soft skills . Focus exclusively on these requirements and you will have a strong chance of meeting the interviewer’s singular objective i.e. ‘good, lets offer you the job’