Well the Republic of China (a.k.a. Taiwan) and the People's Republic of China (the big communist one) would both disagree with this (in principle). Of course in reality Taiwan is at this point a separate nation that some people go to great lengths to conspicuously ignore, but this isn't the "party line" on either side. The revolution in China is still within living memory and there's more than just Xi Jin-pingbots who don't see the status quo as valid, de jure.