They are only moving to other platforms that are harder to track, like Discord or Telegram. Just because they don't appear in the data doesn't mean that they don't exist. Then yes, you sanitize some platforms but the problem as a whole is just less evident but still growing.
Harder to track also means harder to find. Sounds great to me. Let's make sure anyone who worms their way into those dark places knows without doubt that they're detestable, that civil society stands united against them. Maybe with some time, the boredom of the next generation can be directed to less evil ends.