Why is Mandarin spoken in Taiwan and not popularized in Hong Kong?

China's Taiwan last century, the mandatory implementation of decades of the national language, such as schools are only allowed to teach in Mandarin, the media are only allowed to broadcast news in Mandarin, etc., coupled with the Taiwan last century and the emphasis on traditional culture, so Taiwan's popularity of Mandarin to reach more than ninety percent.

Even after the so-called democratization of Taiwan, the Taiwanese society considered that Mandarin is still suitable to continue to be used as the language of public **** and convenient for cross-strait exchanges, so it is still spoken in official occasions, but the protection of local dialects has begun to pay attention to, including the Minnan language, the Hakka language, and the minority language of the Gaoshan people.

China's Hong Kong was colonized by the British until 1997, and before that there was no policy to promote Mandarin. After the handover, because of the high degree of autonomy under the "one country, two systems" principle, Cantonese and English are still taught in school classes, and the rate of Mandarin popularity is still not optimistic.