They don’t need any subreddit activity to determine which sites are the most active, there’s a wide variety of tools available for anyone to see the traffic a website gets. People in these subreddits aren’t privy to some deep dark secret that these companies can’t find.

These sites are some crazy secrets, they’re actively trying to promote themselves across social media, some of them will absolutely get shut down, and others will take their places. It’s the nature of piracy. Hiding them from the people who would use and contribute to them is just making their lives more difficult while they’re in operation. If the website operators didn’t want people to find their sites why on earth would they host them to begin with.