Actually, I don't think the "free speech" argument as deployed in defence the unmoderated promotion of fascism actually has a coherent concept of quality: the entire point of the argument is there will never be a time when an idea can legitimately be locked out of "the market", because there simply isn't any fair way to judge ideas.

Whenever the market idea is mentioned, it's always to invoked the principles of unregulated exchange, and not to remind readers of things like legislation about quality control for products to enter the market. And it is always argued that this market should have a constant and unceasing exchange (and more to the point that their particular idea should be given more space), so this isn't a market that works toward a consensus but rather a site that needs to be maintained in constant conflict.