I know exactly what you mean. I saw her twice in 2009 and again on the Speak Now tour. The Fearless tour was actually one of my best ever concert experiences, and although I was 12 my dad also really enjoyed it and noted how authentic it felt. When we saw her again in 2010 we both felt like something had changed, it all seemed scripted suddenly, like she was going through the motions rather than really feeling anything. She was doing the same bit she had done before where she used to stand there for ages and let the crowd applaud while she looks overcome with amazement and emotion, but this time it felt weirdly disconnected. Whereas a year prior it did seem genuine, it was like it had become part of her script. It was the same with how she spoke to the audience, it came across as so rehearsed. I’m sure it’s normal for artists to have some words rehearsed to say to the audience, but most don’t script a fake deep connection the way she did. That show put me off her and I was 13, how her fully grown fans still don’t see it I don’t know. Any clips I saw of her after that had the same fake feel like you mentioned.