Theorizing about things going on in TV/movies/books that may or may not ever be confirmed in canon is a favorite pastime of many fans. But some fan theories take the fun out of things rather than inspiring fun conversations. Analyze what features or circumstances, if any, make a fan theory "worth considering" or not. Examples to consider include Jon Negroni's Unified Theory of the Pixar Theory, the 007 Codename Theory, and any of the "They were dead the whole time" theories.
This is an interesting discussion, and fan theorizing has certainly boomed alongside social media. It might also be helpful to consider how fan theories might have an affect on ongoing creative work. Fans often theorize what might be happening in a show or series before the finale is written. Do writers ignore these theories? Do the intentionally thwart them? Or do they read fan theories for inspiration? – JaniceElaine3 years ago
One pro I find is that several fans (presumably from all over the world) are able to geek about their respective fandom, and get together and engage in whatever they are discussing. It is a great way to discuss new ideas, and further immerse oneself into the show/game/whatever a group is talking about. One con, however, is someone can go too far with proposing a theory and not letting anyone discuss their disagreements with said theory. People are allowed to have their own ideas, but only if they are allowed to open up criticism to the theories they present. – DrSpaghet3 years ago