Striving for normality... such a tedious cliché.
Why not just call it like it is? Striving for mediocrity. Championing the perceived superiority of NOT being superior. How very Japanese. Because someone couldn't possibly be happy by being naturally good at things. ¬_¬
The point is that she wasn’t happy being good at school, she would have rather been taking photos and making friends. In contrast Shirogane was perfectly happy being good at school, so it isn’t even saying that people can’t be happy being good at things, just that people should be happy doing what they are doing, whether they are good or bad at it.
I bet the reason that this is a common Japanese theme is that their work lives are very serious and crushing, and so they often wish that instead of putting everything into school, they spent time with friends more.