Let's say you hold extreme anti non-white, anti-Muslim or anti-immigration views that "justify" violence towards Australian or New Zealand citizens or residents...
Does the fact that there are anti-Western/anti-Christian/Islamist extremist views out there mean you are safe to advocate violence? No. Both extremes are wrong. Extremism is wrong. Let the police and security services do their job, and use the democratic process to push any legitimate view you have in front of voters.
After the Christchurch incident, some may want to look at some of their past posts with the view, "How would the Australian Federal Police interpret that under section 5.3 of the Criminal Code?" In the context of a major terrorist incident so close to home, they may be already looking at that.