I avoid even comparatively mild stuff, e.g. Godfather or Dark Knight (peeking at IMDB's top movies), and have done so for decades. It's a conscious decision, one I made in my twenties and not in any way related to aesthetics, anxiety, being childish, or mental issues.

I'm not really advocating it. I don't claim it gives superpowers or big benefits (and if anyone claims them, I'd ask for hard scientific evidence), but I can just say that any life decisions differentiate a person, even if by tiny bit. Looking at the whole population, life decisions make people diverse and drive them to bump against each other, which is mostly fun, no?