Well, first I agree with you -- he should get vaccinated. But I've talked enough with him to understand a few things.
First, the media has been all over the map about whether vaccinated people can spread the virus -- even the New York Times had a piece that said they could. Twitter went nuts, and wondered if the NYT would have to take down the tweet because it was misleading. But the bottom line is that because he's seen more than one media story saying that vaccinated people can spread it, I don't think it registers as selfish to him to not get it. He otherwise wears masks and complies with all other protocols.
Second, as someone who is deeply pro-choice, I have to respect his right to bodily autonomy. I might not agree with his choice -- I don't, in fact -- but I can't on the one hand insist he do something with his body, and then insist that others have no right to tell me what to do with mine.
But finally, refusing to go to Vegas, or declining to have sex with MAGA Man was never going to change his mind about whether to get the vaccine. We just wouldn't have gone to Vegas, wouldn't have had sex, and he would still remain unvaccinated. If we truly want to get more people vaccinated -- and I really do -- then seeing the people as whole, complex human beings and understanding their motivations and concerns is really the only way to go.
You're obviously -- as is everyone -- free to decline any experience you want. I wanted the experience of meeting this man, because I'm trying to live in a place of curiosity about folks on the other side of the Great Divide. I think it ultimately helps us all in the end.