It's impossible to say. On one hand she would have been the right age to be a fan of Justin Bieber or One Direction. She was after all a young teenage girl when she was wrote her diary.
On the other hand she writes about enjoying classical music (specifically Mozart), which would have been considered old fashioned even in the 1940s. But of course, it doesn't have to be one or the other. I can tell you from personal experience just because you like classical music doesn't mean you dislike other genres.
I love Beethoven, Mozart, Saint-Saëns, Prokofiev, Tchaikovsky, etc, but I also love The Beatles, Led Zeppelin, Queen, Pink Floyd, and so on.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.