Well Taiwan was Japanese from 1895, ceded to Japan after the sino-Japanese war. Even the leaders of Taiwan can speak Japanese and Japan has clearly said it would come to Taiwan's aid if China attacks, which is actually a stronger official position than America. Australia has also declared the same.

I get it, you are overseas Chinese trying to find your identity. Being overseas you can say whatever you like without fear or restriction, unlike in mainland China. You have no great firewall of censorship. I encountered the same thing with overseas Russians, even overseas Serbians, Greeks and Italians. It is a coping mechanism that you are more nationalistic than even the people in mainland China.