At least, I can’t think off the top of my head why there should be anything particularly worrisome about people believing that there’s a large monolith on Mars. Oh, sure, you could link it up to something vile – but by itself it’s pretty harmless. There’s a monolith-shaped object on Mars.
Standing tall, and… monolith-y.
Not falling over, or anything like that.
See what I mean? If you want it to be about the Templars or the Jews, you sort of have to port it in.
PS: The Martian Enigmas: A Closer Look: The Face, Pyramids, and Other Unusual Objects on Mars Second Edition. Only because there’s a Second Edition.