Ah, SDN, sweet font of bad information...
OP- UH is hard for mainlanders to get in to, but not impossible. Last year, 1,112 non-HI residents applied, 114 were interviewed and 9 matriculated. What's interesting about those numbers is that they interview a LOT of people for very few slots. JABSOM really does want the right mainlander for those slots.
If you are only interested in four years of fun in the sun, you'll be weeded out. Many mainland applicants have some ties or others to the state. If they don't think you'll want to practice medicine there, they won't take you.
Do not judge Hawaii based on impressions of people who have not lived there. You can not get a good take on the islands from visiting, no matter how many times.
Hawaii is not islands full of racists, but it's not oasis of racial harmony either. Aloha is still there, but not as much as it used to be. It will take you years, if ever, to feel a true part of the community there, just because so many come for a few years then leave.
Lovely place, good people, good med school. Takes some getting used to to live there.