“Horror movies” is an extremely broad term and would include everything from the 50s campy alien films like “The Blob” to exorcism movies to psychological horror films like “Carnival of Souls” to slasher gore films to old classics like Bela Lugosi as Dracula, etc. It’s fine if you simply don’t like the genre or are sensitive to it and thus avoid it, but with such a huge variety of films, subgenres and treatment of subjects, the idea of them all being damaging is far-fetched to me. if you are a film aficionado, you’re going to want to watch some of them simply because they are very good movies, or very bad movies, from a filmmaking standpoint.
Also, some of them are making broader points about society. “Frankenstein” is a classic in that regard, and the 50s alien and monster movies are generally understood as relating to WWII and the Cold War.
It’s also fun when you recognize the places in the movie. I was just watching the original Steve McQueen version of “The Blob”, which was filmed in the 50s around a couple of towns where I have spent time, and got a chuckle out of seeing a poster for St. Joseph’s Church annual festival in the diner scene. St. Joseph’s Church is still there, albeit in a much bigger and newer church, and still has a huge festival every year. I also enjoy watching the original “Night of the Living Dead” as it was filmed near my husband’s hometown, the name of which appears in the news broadcast scene when they are showing the list of emergency shelters. My graduate school program was located in the building next to the “Exorcist Steps” and the locations in that film are very familiar to me as well.