You miss the point. Rudd used to advocate engagement, and now he advocates full spectrum containment. The OP mentions the disappointment of this hawkish turn. While most inside the beltway has turned over the past few years, Rudd has tried to put up a semblance of neutrality and objectivity. Now he openly calls for the US and its allies to bully China, as the OP puts it.Nothing strange with what he said. US' hegemony depends on Taiwan. China getting Taiwan would be catastrophic for the American Empire.
Any amateur geopolitical watcher will tell you that Rudd's talking points make sense when viewed from the American perspective
I don't need an amateur geopolitical watcher such as yourself to tell me what the american perspective is since I'm from the US.