I’ve written about this stealthy attempt at censorship before, which the GroundUp website has kindly published.
I think there’s a more general discussion that needs to be held.
The ISPA provides, through it’s code of conduct, a process for its members to take action against “Unlawful content and activity”. “There is no general obligation on any ISPA member to monitor services provided to customers, but a member is obliged to take appropriate action where it becomes aware of any unlawful content or conduct.”