RISC-V has some extension instructions dedicated to them. The extension was ratified very recently, so it isn't clear which chips will actually support them.

> Facebook

While FB have many customers in China (much as Google do), I don't believe that they have any actual data centres, and they certainly don't have any (official) users.

They're just horribly modified versions of western standards. And no they're only used by governments in China. The general public still uses TLS.