They’re not suing Netflix for the format, they’re suing them for using the phrase “Choose Your Own Adventure”, which is officially trademarked. The genre itself isn’t owned by anyone, but if companies wanna make their own gamebooks, they have to call it something else, like:
Also, apparently, Netflix has been trying to get a license to make an official Choose Your Own Adventure movie for years, but ChooseCo wouldn’t give it to them. So, when Netflix made a Black Mirror episode that actually said “Hey, there’s a Choose Your Own Adventure book author who went crazy and killed his wife!” they uh…