I would see it differently.
From one of the departure charts, for example,
http://www.hkatc.gov.hk/HK_AIP/AIP/AD/HK_AD2-97J.pdf, 5000 ft or below is not a level restriction for PORPA/ROVER or TD, even the CAD published database coding has it.
I supposed it is just there for the awareness of the 5000ft initial restriction.