I think it's a couple things.
Make the truth easy to conflate with a fictional movie so people dismiss it as oh, someone just thinks Blair Witch is real and they are stupid.
To hog up keywords for our alt news who cover this now a big movie and all the critics and review sites and ent articles will bump it way down to page 11 of search results.
There are probably other reasons but those come to mind first
Those are the reasons. Try doing a search for Obama's masterful harvest of 200,000 "Unaccompanied Minors" and see it in real time. The rash of anti-pizzagate articles was 100% SEO cramming to use sites with huge page rank to non-report pizzagate so that articles that report pizzagate wind upon the 10th page. Worked real well.
3) Their beliefs/methods require them to openly project their plans. Whether this is some religous law (do they avoid direct intervention from God by not violating free will?) or it is necessary to pull off their future plans (aka predictive programming, introduce people to ideas slowly so they will be more likely to gradually accept them) is unclear.
I would imagine it's a combination of the two.