See the edit reason I gave. To expand on it: Some weren't film rivalries, or spanned film and TV ("Star Wars vs Star Trek" existed before there were Star Trek movies), some outright conflicted with established entries elsewhere on the page (the cluster of horror movies, specifically -- the first entry under "Friendly Fandoms" lists all those and more as a group of mutually friendly and reinforcing fandoms), many were linked to non-film properties, and some don't actually exist to the best of my knowledge, regardless of media reports. And because it was a plain unadorned list with no contextual information unlike every other entry on the page.
I see that you have restored your contribution with footnotes, which we don't use here. If you want your addition to the page to remain, I recommend that you actually spend the time to write a paragraph on each "rivalry" instead of resorting to quick and lazy footnoting. I would also recommend you actually link to the right pages. And restrict the list to actual rivalries between film properties. We'll let it stand for now, to give you time to correct/improve your contribution, but if you don't bother, it will be deleted again.
I would also strongly recommend you not edit-war with the moderation staff. If I or another mod removes your contribution for any reason, putting it back a third time is a fast trip to getting your IP tempbanned or worse. Consider this fair warning.
-- Looney Toons
CC: @Labster, @GethN7, @Robkelk, @QuestionableSanity, @Derivative, @SelfCloak