So, I don't think it's as big a leap as it may seem. Bear with me a moment:
Modern communication between individuals relies on the internet. Even the government has acknowledged this, insisting that all of their services are available online.
All spaces for communication on the internet (including elements as low as DNS and hosting) rely on private companies.
Private companies can and do take censorious actions based on values that, at best, are layered upon the values of the country that the company operates in. However, at worst, the company's values need not have any relation to those of the countries they operate in.
Thus, the individual's freedom to express their thoughts relies on their thoughts not being censored by private companies. If one of the many companies that you depend upon for communication decides to not let you express that thought, you are unable to express that thought.
Of course, this applies to the internet and not government-owned meat-space, but government-managed meat-space is not where this communication is occurring. Particularly around the incident in Hong Kong.