I think what is hard to explain is how you determine who wins. Most people understand that in "old school" voting the one with the most votes wins. With ranked choice, how does it handle multiple people with very different rankings. Its easy to say "the one that most people preferred" or "instant runoff" but explaining how that is calculated is not easy. I am very much for ranked choice, and I was devastated when it lost the vote, but it's biggest hurdle is comprehension, and that is something for FUD'lers to prey on.