I'm talking a bit about the recent film from DC and, as a result, this post talks about some potentially triggering topics. Read on at your own consideration.
Writers have a hefty burden to bear. It is our job, when done properly, to convey a story full of meaning and power. Stories should say things worth saying, and encourage actual change in the world. Though so many of us, myself included, tend to write things that are more entertaining and not, perhaps, rising to the level of the "Brussel sprouts" that can be many reading options out there - things that it is good for you to read but perhaps you don't quite want to. Even in our most genre of fictions, good writers have stories that are about something.
The old adage "write what you know" is often criticized as being overly limiting. What I think most writers who adhere to it and argue for it is, functionally, "don't write what you don't know". This can extend to emotional challenges beyond your scope or to facts. You can fill in those blanks that you don't know, but writing without doing so leaves you open to all sorts of silly mistakes.
These are our blind spots and, to paraphrase a political figure that I'm not a fan of, we don't always know what we don't know. It is only through extensive reading and research topics we don't know as well that we can learn these aspects of what we don't know.
Failure to do so results in things like DC's latest animated foray, The Killing Joke. As I read interviews with the creative team behind it, they admit that they didn't consider all sorts of things that ended up being in the final product. A writer suggesting that he never considered certain lines as implying that someone was sexually assaulted, and would not have included it had he thought this, is a definite failure on their part. We're just as responsible for things that are not intended but still happen in our work.
Research needs to be done, needs to be pushed to the point where you almost feel like you've overdone it. Drawing on your own experience or the experience of others, that counts as research. You just keep going that way, trying to make your work better and better.