DNSSec is entirely useless here. The government has two goals here: block you from accessing certain sites, and perhaps prosecute you for the attempt. DNSSec does exactly nothing to help against either of these , even if perfectly deployed.

DNSSec can help protect from fraudsters or others that might try to transparently direct you to a different site than the one you wanted to access. But the government here has no intention of serving you a fake porn site, they want to stop you accessing porn and log the fact that you were trying to access it.