The real reason English is fading in Hong Kong: the rise of Mandarin?
The level of English language skills in Hong Kong is a popular and perennial subject. This article mentions that native speaking English teachers were common in local schools in previous generations. Yet the article suggests that the pressure of learning Mandarin has been the main cause of a decline in English. Perhaps there is a correlation between a decline in the numbers of native speakers employed as teachers rather than the prevalence of Mandarin which has been the main cause.
It is difficult to know how this can be addressed. Clearly English is important in Hong Kong but so is Mandarin and it should not be a choice between one or the other.