Which language will you use to write the CLR then? C# itself? Yes, it's doable. But then you can't use CLR to run your CLR implementation in C#, or it never ends. So you have to compile your C# code to binary, and consequently you can't rely on the features of CLR, such as memory management, what's the point of using C# then?

If they were all shot which OS would we be using right now?

No, the entire thing is made up. China is an extremely poor country and it only has one power generator, which is in Zhongnanhai and only used when foreign leaders come to visit. No shock therapy is possible in China, the average Chinese have no idea what electricity is.