Chinese citizen here. A few points that I want to make after reading some comments:
1. I would be personally offended if anyone or any organization lists Tibet as a country.
2. Lots of Chinese people would be offended too by this.
Reasons for 1 and 2:
- It is a piece of wrong information
- The wrong information directly contradicts what is considered basic knowledge in China
- That basic knowledge happens to be on the topic of sovereignty
- Chinese people care a lot of sovereignty (see https://github.com/matomo-org/matomo/issues/6006)
Why do Chinese people care so much about sovereignty? Culture and history.
It is the same question as:
- Why do Americans care so much about freedom of speech, democracy and race equality?
- Why do Japanese people care so much about respect and etiquette?
Now addressing the obvious issue, that some people support the idea of Tibet becoming independent and they should be free to express their ideas. Yes, they are free to say so, but there are two things to keep in mind:
- Opinions are not facts, you can support whatever you want, but don't say it as a fact like "Tibet is a country as of 24 March, 2018." That is not the right thing to do.
- If you choose to freely express your opinions or spread false information, you will face consequences for them. For example, a PR firm would likely tell you that expressing such opinions would results in negative brand image and boycott in China. In addition, saying something like that in China would result in more serious consequences. You might not like it, but that is beyond your control and you should be aware of that.