@jynersolives there are already filters you can select yourself, filtering out certain words and phrases so you don't have to see posts you don't want to.
it's called a content WARNING because it is a warning to people about what the content of the post is. it's great for spoilers, too. you're warning someone that if they click your post, they'll see the content you have described.
i don't see what the problem here is, especially because people on twitter frequently put CW on the top of their posts if it is going to contain stuff some people might not want to read about.
as far as graphic/adult images go, that's why the "mark media as sensitive" button is there. if you were posting something particularly gory, or perhaps a really niche fetish, then maybe you would use the CW button as well.