Japan is a US puppet and this move is meaningless before the office is actually open - until then it's just the US leaning on Japan to make a statement. The previous government you're praising, Abe, unequivocally stated Japan would not participate in a military defense of Taiwan.
Even the current foreign minister seems more focused on Russia in his statements, which Japan shares a border with, than China, and seems to want to stop this sort of speculation before it begins.
You present Europe, Taiwan, and Asia to be more anti-Chinese than it really is, and for battle lines to be more solid than they are.
No one outside the US security establishment sees a China-West Cold War as desirable or an inevitability. People want to live their lives, maybe visit Mars and solve the issue of climate change.