Who's to say there ISN'T influence?

FRAME CHALLENGE: One of the most common tropes in literature (or conspiracy theories) is the idea that people are currently manipulating society to fulfill their own visions of the future. Aliens, vampires, Reptoids (if you consider them separate from aliens) and the like are all portrayed as quietly shifting society, and that they have been for decades, centuries, or even millennia.

It is FAR from clear that a masquerade requires a prime directive. In fact, I would argue that a masquerade would REQUIRE interference in society so evidence disappears, un-cooperative public figures disappear without leaving evidence, or people are given plausible reasons WHY that video showing vampires feeding is an internet hoax. The media would be influenced, leaders influenced, and possibly (like in Men In Black) large portions of the populous directly influenced.

So maybe L Ron Hubbard was a telepath and DID start a cult revealing truth, and had to be silenced because of it. Harvey Weinstein? Totally a tool of the Reptoids. The FBI? Most of their budget is spent doctoring evidence to make vampire attacks "disappear."

Besides a rule to maintain the masquerade, you'd probably need a rule requiring the creation and maintenance of a giant conspiratorial organization charged with maintaining the masquerade (let's call it "the Illuminati"). The aliens, vampires, Reptoids, and Scientologists would all need to sit down at a table and hash out who controlled what, how disputes would get handled without public exposure, and what the powers of the conspiracy would be.

In fact, if you DID have multiple supernatural factions to contend with, the only thing likely to STOP a global supernatural war would be an agreement to maintain a public façade or normalcy.