It's very sad. DSM was never strictly meant to be a clinical diagnostic tool, but rather it was originally meant to define specific illnesses in a manner that would facilitate further research by allowing investigators to at least be talking about the same phenomena when comparing results. (and it unintentionally became very popular with lawyers, who argued that presence in the DSM equated to unimpeachable evidence of an illness in a client, another use that it was never designed to accommodate)

It's still true that there are only on the order of 8-12 well-validated diagnoses in the manual. Increases in the number of included diagnoses over editions is primarily due to concessions to important researchers as opposed to clear identification of previously undescribed illnesses.

There are lumpers and splitters in academic psychiatry. Lumpers are suspicious that there are several hundred discrete disorders of the brain that can't be more parsimoniously explained with existing, better validated illnesses.