It was a real moral panic in the 80s or 90s. To be fair, it's one of the less deadly moral panics of the 90s. It got a lot of steam when a private detective was hired to find or investigate a troubled teen and found he had committed suicide, and he wrote a book about it and instead said he had become delusional after playing D&D, thought he was the fictional character of RPd and tried to do things his character could do, but killed him. Eventually enough people pointed out the absurdity of the story and people who knew the kid had grown up and made it very clear he committed suicide intentionally and was never delusional, the author then acknowledged he made up the story, but even more perplexing, claimed the teen met him before the suicide, he made it sounds like mere moments before, confessed to drug abuse, and said he didn't want his parents to find out, so asked him kindly to make up a cover story for his actual actions and motives to protect his family from, or maybe just his mom. Anyway. A lot of people took this seriously, but if you're even slightly aware of what tabletop rpgs are like is like claiming a high schooler who played too much soccer became delusional and thought he was a soccer ball, and kept trying to inflate himself until he died. I'm not saying it's impossible, I'm just saying if that did happen, playing too much soccer wasn't related to the delusional mental health disorder.