But business likes stability. The democracy protests have done nothing for Hong Kong, and now that China's eased access to their market through Shanghai, Hong Kong's entire raison d'être is at risk.
Also, the article is pretty spot on in other ways. Once upon a time, Hong Kong students were guaranteed success by virtue of being born there. Now, they need to compete with mainlanders, which of course is a much larger pool.
And finally, 20 years ago China wanted to build up Hong Kong as a model for it's 2 systems 1 country philosophy. However the democracy protests have all but killed that, so the Chinese will gladly simply build up Shanghai to Hong Kong's detriment, and no amount of democracy or separatism will fix it.