I very much agree with you when you say that one doesn’t have to be an expert. I see plenty of people mainly in the IT field pretend to be experts at things they have no clue about. It’s the insecurity and low self esteem that drives their pretentiousness. One rule I learned in my professional career is it’s ok to embrace that you don’t know. It’s better to say I don’t know other than pretend to know and look a fool.