basically the concept of kyc is used to show the authenticity of data and the legality of the user to use the services of a company. even though it was very privacy but someone faced the choice to do it for his sake. I would rather see Kyc as proof of authenticity of data and clarity and truth that is very useful if someday there is a problem from a service to the user, then it can be checked to the original. I think overall for crypto it doesn't have to be, but for services such as exchanges, banks or services like that it should. for the security of the system too.