Keeping up with JavaScript libraries is a full-time job. Even if you pick one to specialize in, the constant stream of changes made to it is going to make you feel like you're always behind the times. On top of this, people who write about JavaScript and Web Development or make YouTube videos about it will be constantly telling you that the way you're doing things, the library you're using, or the specific features of that library that you're using are ruining the web, killing puppies, and worse.