So let's look at what happened in reality. Almost immediately sub-reddits pop up that are at the very least attempting to skirt the law, and often directly breaching the law- popular topics on reddit included creative interpretations of the age of consent for example, or indeed the requirement for consent at all. Oh and because anyone can create one these communities, the site turns into whack-a-mole.
The second thing that happened was communities popped up pretty much for the sole purpose of harassing's other communities. But enabling this sort of market place of moderation, you are providing a mechanism for a group of people to organize a way to attack your own platform. So now you have to step back in and we're back to censorship.
I also think that this article completely mischaracterizes what the free speech side of the debate want.
(This is for anything with a political slant to it, I still find it useful for niche subjects, say mycology)
It wasn't supposed to be that way. Even the Reddiquette page told people not to downvote simply because they disagree. But nobody reads Reddiquette, and these days most redditors think disagreement is the purpose of downvotes.
That being said, you'd have to be naive to think downvoting for disagreement doesn't happen on HN.
> post throttling
This is only a thing for new accounts as an anti-spam measure.
> over zealous moderators banning people for wrongthink
I think it's wrong to blame reddit for this. This will be a problem on ANY site that allows users to create their own communities within it.