This phrase is a concise way to mean, "My parents still deem the movie 'Threadpool' to be too
inappropriate for me to watch," regardless whether you're still 5, 15, or 25 years old. Here, 'Threadpool' can be replaced by any movie with excessive amount of
inappropriate contents (
vulgarity, profanity, violence, etc.), but 'Threadpool' is among the most common movies for children to salivate at whilst still being too young to watch said movies.