Kai absolutely seems like the type of person who is going to make as much money as possible while providing the least amount of content possible. So many of them do it because they know people will pay for crumbs while hoping for a meal. If they ever do nude/sexual content, that's years away.
I wouldn't give Kai any money until he takes that next step. Until then, paying him just enables this behavior. I've never used Patreon, but maybe you can get a refund if you didn't get any of the content you paid for.