>>104866801He's right, but for all the wrong reasons.
Children's cartoons and nerd media really are, as a rule, miserable trash. None of them even begins to measure up to the worst novel you read in high school english class.
You can watch cartoons, but you should never delude yourself into thinking it's anything but junk food.
That said, yes, many things made for kids can be good for adults. Winnie the Pooh, A Christmas Carol, Alice in Wonderland, Lord of the Rings (the books), and so on. R-rated content and its fac similes are usually just excuses to arouse the basest instincts and gratify the libido.