PHNL was a joke from the get go. The siting was pure sand.
Lots of manned obs were trash too. MHT ran too warm for years before ASOS. Lots of bad COOP data too. I think CON was on the side of a brick building in the 1800s. Wherever you look you can find bad obs in different eras.
The ASOS temp is very accurate, but like any readings, it’s only as good as its siting and maintenance.