Ah, of course, a mistake on my end. I mixed up Honolulu, the city, and O'ahu, the island while looking up the plus-code due to misinterpreting Google Maps' peculiar choices of font cues for countries, islands and cities. I am not very familiar with Hawaiian geography.

Honolulu was the only large name on the island, with O'ahu being written in a similar font-size to all the other cities. Of course now I can see that the cue is that the island name is written in black, whereas cities are written in very dark grey...

UX, yo.