So the way I’ve understood it is:
Although there is no active combat (to my knowledge), since there never was a peace treaty, China is still in a civil war, which is currently being fought by the communist (PRC) and capitalist (ROC) “factions”, so to speak.
This means that both the PRC and the ROC are part of China.
Since a majority of countries declare that the sole legitimate government of china is the PRC, this makes the PRC the legitimate government of China.
Taiwan is not a separate country from China the same way that Fascist Spain was not a separate country from Spain during the Spanish civil war.
Is what I wrote here correct, or did I misunderstand anything? Any corrections are welcome.
From wikipedia, the agreement between the Chinese Communist Party in mainland China and the Chinese Nationalist Party in Taiwan was to recognize Taiwan as a province of China, but not to make a formal agreement on the governance of Taiwan. The pan-green coalition of political parties in Taiwan want independence.