Although the High School Musical movies are funny and remind people of the comforts of childhood, they are not true stories according to Tim Obrien.
Nothing about the movies is vulgar or embarrassing. The only drama that is present is minimal social conflict or desire for a material object. After each movie, there is often an uplifting message that is conveyed through action or song. One of the most memorable is the song We're All in This Together which is shown at the end of the first HSM film.
I think if Obrien saw these films he would laugh. There is nothing about this series that is true by his definition. HSM does not dive deep into the lives of the characters to show all of their imperfections and faults. This makes sense because it is geared towards a young audience, but I still think Obrien would be unimpressed.