I am not saying it is difficult to understand. However, everything is about the margin, and the marginal voter might be confused that he is suddenly using numbers on his ballot where he previously used checkmarks. Maybe that drops turnout from 69% to 67%.
Is it so absurd to think that it is possible that 2% of the voting age population really is that stupid?
Speaking as someone who lives in a city that has already been using IRV for its city elections since 2013 with no drops in turnout or serious issues at all I can only reply "LOL".