Here in Shanghai apple.com has been blocked for some time, and by that I mean it still pulls up unformatted webpages, but all the links and photos are gone and it's just the text. FWIW, If I open iTunes then I can still access the iTunes store that way.
Much more aggravating, for me at least, is that the software updates are blocked and I can't download the latest versions of iTunes or iOS for my iPhone.
And yes Taiwan is a country - the ROC - with its own democratically elected government, legislative system, currency, passport, flag, and military defenses (courtesy of the US)! 😉 Towards the end of the Qing Dynasty the Manchus claimed it as a "province" of China, although they never ruled it directly and ceded it 8 years later after losing the war with Japan. It was then a Japanese colony for 50 years until 1945. So China's claim on Taiwan is spurious at best, considering that the Qing themselves were foreign rulers and not really Chinese.
Hong Kong was officially returned to the PRC in 1997, under the aegis of "one country, two systems" but retains its common law legal system, democratic elections, independent judiciary, free press and media, currency, flag, and passport.