Reading this article again reminds me of some discussions of this topic when I was working in an English language school in London during my working holiday.

Once my colleague who moved from Penang, Malaysia asked me if we use the “-ite” suffix to call ourselves (i.e. Hongkongite). She said the demonym of Penang is Penangite and so she guessed whether Hong Kong people use this too as both places share the “-ng” ending.

I told her I had not heard of that and asked if there are any major places use the “-ite” ending for their demonyms. She replied, “Moscow. Muscovite.”

Another time was that another colleague asked about it and we came up with a conclusion that “Hongkonger” can be used as a noun and “Hongkongese” an adjective. This is how I use the terms now.