There was something else still: the population of Crimea was mostly Russian. Like, really Russian. Using only Russian language, calling hryvnas rubles, and in general feeling Russian. Many of these people actually liked the idea of Crimea being a part of Russia (at least before the invasion - things changed a bit since then). In HK the situation is completely different: people know what kind of country China is, and will fight for whatever rights they still have.
