RE: Although subjectively downvoting posts to zero is anathema to me, the Layer 1 ability to do so must remain (for now at least)

Absolutely! We, the consumer are at liberty to consume.

That said I worry about the volume of non-sense that often get rewarded by massive upvote. Not only it makes us look bad (like a conspiracy platform full of shady people), but also most of these folks sell their rewards immediately and therefore are a drain in the system. I don't even feel they believe in the "snake oil" they are peddling, smooth, they do it because it pays handsomely!