If you're talking about Ronald Reagan, he literally won or tied in every age group, except for the 18-21 block, which he lost by 1 percentage point. https://ropercenter.cornell.edu/how-groups-voted-1980

Friendly reminder that ageism is a ploy used by capitalists to distract from the only meaningful difference between groups: their class. Because the Boomers are gonna be dead pretty soon and posting memes blaming them for societal problems which existed before them and which will exist after the fact is going to do about as much to improve the material conditions of the world and the people in it as it does today. Which is to say: dick all.