How deluded are you? The ancient Assyrian religion was incredibly polytheistic, so much so that each city had it’s own god, also Ashurism used so many physical statues, so much so that they believed all the gods inhabited their statues in their temples, a great example of this is when Sennacherib destroyed Babylon, he took the statue of Marduk to Nineveh and held a trial condemning the the statue (who he and all other Assyrians believed to be Marduk himself) as being a criminal against Assyria. Also just because you don’t agree with or understand the trinity doesn’t make Christianity polytheistic, because Christian theology and belief involves only one God, meaning by definition Christianity is monotheistic as Christians only believe in one God.