I.e, hardly make any loans at all! Most people agree that access to credit has greatly increased the wealth of our society. Not everyone agrees - but I believe this is the consensus.
> They do not need to exist and their services are a net negative on society
Perhaps, perhaps not. The more information that a lender has about a potential borrower the more specific they can make their loan assessment.
Without a credit history, lenders will have to rely on averages. Some people will win from this (e.g. people who "look" like good borrowers on the surface) and some will lose (people who "look" bad on the surface, but have a good history).
The likely outcome if we remove this background information from a lending check will be more misallocated credit.
To be clear, I'm not really arguing that "credit agencies" in their current form should exist, but some sort of information about borrowers is useful to improve allocation of resources. Perhaps each person could manage their own signed Merckle tree of information...