You seem to moderate a weird, niche pro monarchy community, so don't be so surprised when you find that people here don't love it. It's open to the public, anybody can contribute, upvote, downvote, etc. You're likely just seeing other peoples' responses to what you're putting out there.
Now it is possible that it's bots or malicious actors, but it's more likely that people just don't like monarchism. For the right reasons, monarchies are outdated and fucking stupid and this doesn't even seem like an ironic joke community, so they're downvoting it.
I'm sure you're gonna deny all this and still insist that you're being fucked with, but this is what it is.