You mentioned that for many of these efforts bypassing censorship trumped secrecy concerns. Is this still the case?
If I were a citizen regularly bypassing censorship of an authoritarian government, I’d be concerned for my safety if it was well documented that I regularly accessed censored material.
People are arrested for producing things that are deemed potentially destabilizing for the regime/country, but nobody as far as I know ever got arrested for accessing blocked materials.
Of course, if you are also actively producing content it would be much wiser to camouflage your identity much better, if you can. That's when the secrecy becomes a major concern.
Yes, it's still the case, but how bad is a matter of debate.
To make it specific, we can use two criteria to evaluate anti-censorship circumvention tools: (a) How cryptographically robust it is? (secrecy) and (b) How well they can avoid detection? (visibility) The situation is complicated, since they are related but independent.
First, OpenVPN has good secrecy, but high visibility, since it's handshake is obvious, and it even led to a complete block. Second, everything that exploits a bug in the DPI system will have circumvention capabilities, but bad secrecy and high visibility - ultimately, the fact that a TCP connection has been created cannot be hidden, and the fact that you are bypassing censorship will be clear - on the other hand, high visibility doesn't necessarily mean it can be blocked (fixing such a bug can be difficult). [0] Third, a protocol with cryptographic flaws (such as not providing good protection against ciphertext modification) can otherwise have low (or high) visibility, but allows attackers to compromise infosec in some ways. Finally, Tor has circumvention capabilities, excellent secrecy, but high visibility - it's anonymity depends on its large anonymity set, not hiding the fact that someone is using it (which is unpractical), and its network is completely open.
Primarily, my personal concern is whether the circumvention tools are cryptographically robust, so that my secrecy won't be compromised when I browse a HTTP website (The NSA can always wiretap at the exit node, but at least it should not be vulnerable at the entry point). I don't trust these tools, if cryptographers kept discovering implementation flaws from established protocols, why should I trust a tool with ad-hoc crypto? For example, Shadowsocks did not have any forms of forward secrecy, if someone is recording all the outgoing traffic, and later take control over my computer, using a single key allows the decryption of everything. On the other hand, some people argue that flaws may exist, but exploitable ones are rare. But still, I think it's a bad practice to lower the standard of secrecy. If I have to use them, I'll run an additional layer of TLS on top of these tools, so that my connection will always be as secure as TLS, while the outer layer provides circumvention. Fortunately, most people are protected anyway by HTTPS.
> If I were a citizen regularly bypassing censorship of an authoritarian government, I’d be concerned for my safety if it was well documented that I regularly accessed censored material.
If your goal is totally avoid detection of using any circumvention tool at all, it's going to be much harder. Many privacy tools are developed to exercise one's rights to privacy, but they are not designed to avoid detection. On the other hand, the same tools are usually promoted for citizens in oppressive regimes. This can be dangerous. For example, a full-disk encryption software that includes clickable links to its official website, with automatic update, what can possibly go wrong? If the regime is authoritarian enough, the regime can simply make a list of all users that have accessible to these servers before and hunt them down.
A huge amount of work needs to be done to fix this problem. However, if you are in China, it's not that dangerous. In the authoritarianism spectrum, there are Kazakhstan, Iran, China, Russia, and others. However, China is nowhere close to the extreme. Being economically open at large, the censorship of information in China cannot, and was never meant to prevent all forms of access. The purpose is merely to increase the costs from doing so. In fact, criticisms of the government in domestic social media are sometimes tolerated, often the censorship only kicks in when it became popular.
By installing an Internet censorship system in China, the consequences are: (a) Most people are not interested in accessing block websites, at not in a regular basis, even if methods are available. (b) Accessing information doesn't necessarily mean a change of point-of-view, especially when the opinions are completely different from one's education, personal experience, or worldview. (c) Foreign platforms cannot gain any significant influence, even if they are accessed to many. For example, the Chinese Twitter community is an interesting place (if one digs deeper below the political flamewars at the surface), you could see people coming from the entire political spectrum. There are even jokes, such as "Twitter - the future of governance in China", but they are irrelevant in the big picture. (d) IT workers are required to use Google and other blocked sites for doing one's job.
Under this background, regularly bypassing censorship in China just for web browsing is perfectly safe [1]. If you want the best invisibility, I recommend you to use the most popular VPN service used by the highest number of people, and run your own encrypted tunnel inside that. The downside is that these services are too popular to be stable, most IT workers still prefer to use a personal hosting service.
[0] Due to the increased centralization of the web, changes are expected. With SNI encryption, if all the censor can see is a connection to an unknown website on CloudFlare's server, it's less of a threat. But different opinions exist, one says the pressure of censoring everything vs. not to censor can lead to an decrease of censorship or a faster overthrow of the censorship system , but others say the censorship/anti-censorship forces are in a dynamic balance, the introduction of centralized services with SNI encryption can actually break the balance. What used to be a slow censorship progression that needed in 5 years can speed up to 2 years, creating an accelerated and more aggressive censorship, and ends up to be a net negative everyone. Whether it is the case is yet to be seen.
[1] Unless you are in regions like Xinjiang, where separatist conflicts are seen as a threat, and that the censorship has extra objectives.
