What should ‘count’ as a disorder?

The DSM-5 was recently updated. The update includes a new disorder called “Prolonged Grief Disorder”.

You can read about the new disorder and its critics and proponents here: https://www.nytimes.com/2022/03/18/health/prolonged-grief-disorder.html?referringSource=articleShare

What do you think about naming this experience a disorder? Do you agree that Prolonged Grief Disorder belongs in the DSM-5? Why or why not? Write approximately half a page to provide your response. /1
Some things you could consider in your answer include:
“Medicalizing normality” (slide 26 in Psychological Disorders slide deck A),
The different conceptions of mental illness (slide 3 in Psychological Disorders slide deck A),
“To diagnose or not diagnose (slide 13 in Psychological Disorders slide deck A)
“When a diagnosis is valid” (slide 14 in Psychological Disorders slide deck A)
“Why diagnose” (slide 15 in Psychological Disorders slide deck A)