What many people are saying is correct, but it's only half the story. Since, well, ever, people have made fun of Ohio because it's boring and had absolutely nothing to do in it. There was this popular meme where the destinations to see in Ohio was meeting Scott the Woz, a YouTuber who makes a show of the same name, and immediately leaving.

Eventually, there was that trope of "Only in Detroit" memes of absurd things getting stolen. Eventually, the format branched off into other states with things they're known for, including ironic memes of Ohio having nothing to do, and being absurdly boring. Eventually, someone subverted the Ohio joke and had a video of something...very strange, and unnatural happening in Ohio, with the phrase "Only in Ohio". People loved the subversion so much, everyone joined in, and now the original point has been lost, now, to meme culture, Ohio is now a place where aliens invade monsters ravage the street, and dogs have three legs.