It adds to the cohesive narrative which can make the overall story telling experience better. When works are considered canon, that’s usually an indicator that the overall franchise narrative is being cared for and thought of.
It can also mean that some aspects of one show can show up in another or vice versa. It’s very cool to see a character you really like. Show up in another medium.
I fully agree, but I also think that there’s too much focus these days on official canon. Copyright might mean that only one big giant corporation is allowed to make stories “set” in a particular universe, but that shouldn’t mean that fans can’t decide for themselves “nope, that was lame, I reject that particular bit.” And if enough fans share that opinion the big giant corporation might want to listen to them.
Would love if multiple authors could create a shared open IP, where anyone can create commercial works derived from it (as long as they dont copy and re-publish the work itself), without needing permission from an IP holder for every work. And canon and fanon is the same thing, if an author writes a plot, that work would gets rejected or included by other authors opinion of it.
1632 series did kindof that, I think, in that they publish fan-fiction and refer to it in main stories. But thats just through one publisher. And did the fan-authors get royalties for that book sale? Idk.
For your second point, you can do that without worrying about canon. In fact it’s easier if you don’t.
For the first one, that can be interesting for a single coherent work with a single writer or team of writers that planned out at least an outline of a story beforehand, but there are rarely questions about canon for those kinds of stories. For something worked on for over half a century by hundreds if not thousands of people many of whom have very different visions for what it should all be about, in my experience it just leads to people getting mad at each other based on which of those visions they like more, and lots of self-contradictory nonsense crammed into the story to try and make it all work. That is just my opinion though. You are free to like different things than I do.
