
You don’t. You just tell them you’re not comfortable being friends with someone who believes that way and stop talking to them. It’s not your job to make them understand. Eventually when they’re outcasted by enough people they’ll realize they’re the problem and invest time into themselves. Or choose to be lonely and sad their choice I suppose
And genuinely, that is a them problem. Unless you WANT to take on that role, which by all means, if you have the time and energy and willpower to do so I wish you all the best of luck, but don’t feel like you have to. If they don’t understand, then they don’t understand. You told them you don’t want to be friends, so don’t be friends. It’s really honestly that simple