The main purpose of a passport is to allow you return in your home country.
Note that Hong Kong is now part of Communist China.
A nation can choose to either allow you in or not. You may have a legal authorized passport, and a visa from that nation, and still will not be allowed in
I know Communist Globalists hate that individual nations dictate soverignty and their borders, but that is the way it is still in the rest of the world
I found an article how snowden traveled. He got a temporary travel pass from Ecuador. It was obtained in London with the help of Julian Assange. Correa called the pass an “error”.