I disagree, I think the bubble is by design and will continue. Mainlanders will continue to flood into HK until critical mass is reached and then a referendum held to end the 50 Years Rule early, and HK can become a Chinese city under full control of the Mainland, but it was democratically voted for. It's working, as except for the French, net expat migration is outward, and younger local people, a lot who have dual citizenship with Australia, UK or Canada, are moving and some are moving to Taiwan.
At the prices HK properties are fetching now, the yields are in the toilet. In a real world environment it would not be sustainable for this long, so it must be artificial. You can find a bargain here and there, but for the most part everyone's been priced out.