Ok, granted, living in different countries is not something that most people do, so let's talk about the other big advantage that a system with a credit score has. It protects against racism. If you don't have that, it's very easy for a bank officer to reject a mortgage because you're the wrong colour. You'll tell me there's law against discrimination but what often happens is people discriminates and then find other excuses to justify the rejection. Are you going to tell me that this isn't a problem?

Without a credit score that follows simple algorithmic rules, how do you want to prevent this from happening? A credit score that has rules that people know in advance may be gameable but it also creates fairness by making it easy for everyone to know what to do to get a decent score.

Now, the fact is that the credit score could be managed by government agencies (although honestly, I'm not sure any government is much better in term of data security), there could be stricter fines in case of data breach (that sounds like a good idea), but those are implementation details.