I used the word China in other comments because I didn't know what to call it otherwise, hoping that in the context of Taiwan it is clear what I mean
對岸 /duì àn/ 'opposite [side of the Taiwan] Strait' is a neutral term coined specifically to avoid the controversy.
If talking about politics, another neutral way could be to just say 北京 /Běijīng/.
Under no circumstances is Taiwan every seriously referred to as "China," not even "Republic of China," the official name in the constitution, is really used anymore. The passports now prominently say "Taiwan," and polling indicates that "Chinese" identity in Taiwan is dying swiftly with the settler colonialist KMT.
The sibling comment may be referring to political discussions between politicians, especially when talking with PRC officials. I'm not sure, I've almost never heard those terms used except by really weird super-KMT taxi drivers.
The parent comment that "Taiwan calls itself China" is simply incorrect, and the government mentioned, in the 70s, was a KMT totalitarian government that's been essentially overthrown as of the 90s.
It's a pointed issue that you'll often find heated responses from because Taiwan, for basically the first time in its history as a globally participant nation, is finally getting to establish its own identity, separate from the Dutch, the Qing, the Japanese, and the ROC/KMT settler-colonialists. There's great fear that the CPC, having failed to win a culture war here with han chauvinism / han supremacy, will simply resort to violence to imperialise the nation.
So it's both incorrect and disingenuous to say "Taiwan calls itself China."
And so does Tsai Ing-wen:
> “We don’t have a need to declare ourselves an independent state,” Tsai told the BBC. “We are an independent country already and we call ourselves the Republic of China, Taiwan.”[0]
So it's not factually incorrect. Of course the issue is fraught and just saying "the country on Formosa is called the Republic of China" would be completely deceptive, but nobody is doing that.
Talk about Chinese politics is always heated but I don't appreciate being accused of being disingenuous.
[0] https://www.theguardian.com/world/2020/jan/15/tsai-ing-wen-s...
Furthermore, though Tsai Ing-Wen is the president of the RoC, as I said, there's a rising independence movement separate from the settler-colonial government of the RoC. Among these people, and the majority of Taiwanese, Taiwan is "Taiwan," and "RoC" is at best a formality, at worse an unchosen government underwritten by an unchangeable constitution.
The new passport illustrates the point decisively: https://upload.wikimedia.org/wikipedia/commons/6/66/Republic...
If you're unintentionally muddying the waters that's one thing, but I react strongly because I strongly oppose anybody that assists the PRC's cultural imperialism.
It is not. Traditional Chinese is not used in mainland china. It was superceded by simplified Chinese in areas controlled by the Chinese communist party.
This is a rather basic piece of knowledge when discussing Taiwan and Chinese relations.