A lot of science is gonna move to China soon since they are becoming a larger economic power, and also not under a quasi-privatization process like NASA is. A lot of physicists are also very excited about the prospects of particle physics research growing in China.
The world is changing, who knows what it is changing into. Hopefully it's better.
Maybe. It'll be interesting to see what they do about climate change. But I have to think that these world class scientists would be just a little apprehensive about working with a country that'll lock you up if you call their leader Winnie the pooh.
We're talking mainly about physicists, engineers, etc. They're nerds, they don't care for the most part.
Also, they don't even have to like it, they don't have to live there. They can just work there and return every now and then. And it's not like people in China are arrested all the time for stuff, especially foreigners. The worst thing that can happen to a foreigner is typically not getting their visa renewed etc unless something serious happens. And this is kind of typical in many places, academics and students on visas aren't held to the same standards as citizens. They can be both stricter and more lax, because the punishment is usually just deportation for everything. It's an issue in the US too for many people, because while freedom of speech, assembly, etc is theoretically in the constitution, it doesn't say anything about who you can give visas to. So there was for instance last year that Palestinian kid at Harvard who was stopped at the airport and sent back because he was in some FB meme groups where some people had posted pro Palestine memes, or like a few days ago the Chinese kid who had offers from 10 unis whose visa was denied because their dad was a community police officer in China, and there is even a Greek member of the EU parliament I know of who is blacklisted from entering the US because he made a documentary about terrorism which aired on public TV in Greece, and which the state department didn't like apparently. And he isn't even a member of some fringe party, he is a member of very mainstream Syriza. I don't even know if I might be at risk of having a visa denied, if they find out some protests I took part in, or some messages on FB or whatever. People know there is a risk of that sort of stuff happening when they go to some other country for work or study, they're careful regardless.
I have an uncle who went to Saudi Arabia to work there, and a number of family members as well as an old acquaintance who went for work or study in the UAE. These places are arguably worse than China but people still go there. Scientists will go to China if it is the only place where certain research can be conducted.
Finally I don't think China is necessarily gonna be so restrictive for years to come. Lots of people there want restrictions to be relaxed.
As for climate change, China is doing good if you look at per capita emissions. They don't want to have to use a lot of fossil fuel anyways, because the US and allies hold most of them. The issue in China is that many of their larger cities are very very polluted.