Well, a long time back, there are proxies such as fqrouter, GoAgent and XX-NET which sends plain but loaded HTTP requests as transport. So I guess if a country decides to ban/decrypt TLS, people can just switch to another proxy/protocol.

Of course, both fqrouter and GoAgent is long gone by now and should not be used. However, it seems that XX-Net is still been actively developed and (according to their project page on GitHub) is currently give out one million free ChatGPT-3.5 tokens for it's paying user...(I mean like... what??? and why???)