This is bizarre at this point.
Perhaps you wrongly assume that by "China split" I meant "the PRC split" although it is abundantly clear that I didn't.
You can continue to stick to your worldview, or you can admit that maybe the matter is more complex than you thought it was. The point is that there are multiple viewpoints on this and yours is not necessarily the only one and given that you claim not to have a horse in the race it is strange that you would end up carrying water for one of the parties.
Agreeing to disagree is a thing too, you're perfectly entitled to your own take on this no matter how wrong I think it is. But you are not entitled to your own facts and if you really believe this to be an uncontroversial thing then I don't think I can help you with that.
How is that at odds with "facts"? What "facts"? What do you think I claimed? How is it controversial? I am not sure you know at this point as you are being evasive and shifting to ad hominems.
Claiming that the Earth is round is "controversial" to flat-Earthers. Does this make it a controversial topic?
Have you considered the possibility that you are just wrong? Your 'uncontroversial and rather obvious historical fact' is neither uncontroversial nor is it obvious.
That's why we have a 32 page article on the subject on Wikipedia:
https://en.wikipedia.org/wiki/Political_status_of_Taiwan
And it is one of the most heavily brigaded pages there. With edit wars going back as long as the page exists.
As well as articles like this:
https://www.justsecurity.org/87486/deterrence-lawfare-to-sav...
There is only one country where your 'historical fact' is seen as true, and it isn't Taiwan. And that is why China is threatening to invade, and why you yourself use Taiwan without further qualification right after 'South Korea':
https://news.ycombinator.com/item?id=46478045
The 'one China' term itself is overloaded, depending on who you ask (Chinese, Taiwanese) you get different answers.
Taiwan is an independent country, if not de jure then de facto. That China is a much larger and much more dangerous country is the only reason everybody tiptoes around this.