Yes: because of the money.
Diagnosis is tied up with money.
In the United States millions of people use the DSM-5 as a method of getting insurance companies to pay for their services or their medications. They will need some kind of coding to get payment.
Comment from the UK in 2014 about the UK system: "payment systems for services, welfare, housing, social supports, everything would have to change, this gets missed out of dx debates ... even direct payments for non-medical self-directed supports requires a dx somewhere along the line."