When I first started writing, then I wrote what I had experienced. I was bullied as a child. I wanted to show, through my writing, that bullying was a problem that needed to be spoken about, even if I couldn’t speak out myself.
However, It Won’t Happen Again wasn’t born from experience. I found out that someone in my family was a victim for fifteen years. We didn’t find out until she left him. Again, I wanted to create a conversation. For others to see the signs we missed.
So my advice for today – it doesn’t matter. There are writers who didn’t live in the 1940’s. There are definitely writers that don’t live in the future. Yet they write they about a world they’ve created.
What does matter is the research you put into your writing. We are luckier than writers in the past. There is google, and plenty of places where you can get advice, Many books in a library, or even people you know.
I was lucky with mine because someone in my writing group worked in a prison. Another man worked in the police. They both gave me brilliant advice on how to make my scenes realistic.
However, if you do not feel confident about writing about unfamiliar things, then write about what you know. It isn’t up to anyone to tell you either way. The fact that you’re writing is good enough.