The risk of harm will always outweigh the minimal discomfort through free and open discourse that the internet inherently brings with it.
1. It keeps the tech industry domestic
2. The servers are physically inside China, guaranteeing them access to the data
This is why I've always thought that the Great Firewall's purpose is not only censorship, but also a form of Internet-age protectionism.
And American companies seem to go along with it, thinking they have no choice. They do, but they're too scared to lose the Chinese market to risk anything at all, and second, they're too shortsighted to create strong alliances with their competitors to speak out against Chinese policies.
Think about how Microsoft was ecstatic that Google was getting banned from China, believing this would be an "opportunity" for the company to gain market share - it wasn't. Baidu filled out all the vacuum left by Google. And now Microsoft has to accept whatever bullshit policies China throws at it, too.
Instead of allying with Google and others, it thought it can pull one over Google. That's the kind of shortsighted thinking I'm talking about. If American companies want to thrive in China, they need to create strong alliances and cooperate more against bad Chinese government policies, and not sell each other out for some promised short-term gains, that they'll lose in the end to local companies anyway.
What I see is a trend to rebuild on the Internet the same borders that are enforced in the physical world. Some countries will keep their internets open to each others, others are already closing them down partially. They're probably putting them at a disadvantage, especially the small ones, but the governments usually only cares about keeping their seats.