I don't think it's fair to claim KGIII's entire argument has been invalidated anymore than it's fair to characterize it as absolutist (b/c illegal speech was not supported in any of this thread by KGIII).
In the US, maximizing liberty is a priority, but minimizing violence is also a priority; so, these things both have to be considered. If Australia (or any other country) does not share this prioritization for liberty, that is up to their citizens. But, the US Constitution is still the law of the land here in the US, and no matter what those with authoritarian tendencies want for their countries, we will continue to prioritize liberty.
In the US, maximizing liberty is a priority, but minimizing violence is also a priority; so, these things both have to be considered. If Australia (or any other country) does not share this prioritization for liberty, that is up to their citizens. But, the US Constitution is still the law of the land here in the US, and no matter what those with authoritarian tendencies want for their countries, we will continue to prioritize liberty.