They don't speak Hawaiian anymore, they speak english
Yes, that is indeed true, but there IS someone working on a Latin course and that's not spoken anymore either. (Unless you learn it through resources.) Same with the Irish course. There are some people who speak Gaeilge still in Ireland, but there are more people learning it than native speakers.
People still might want to learn Hawaiian though, as goes for Latin and Irish!
True but there’s a few thousand speakers of the Hawaiian language left
Actually, it's mostly limited to one of the Islands of Hawai'i, Ni'hau. At least the closest "original" Hawaiian.
One of my dreams is to visit Hawaii and before I go, I would like to learn at least some of the basics of the language. I've heard it's polite to at least attempt to do so when visiting another culture.