I've been told by history-loving friends and read in books about in early American history, when older men, sometimes in sixties or seventies, would take younger, often teenage, wives, without popular outcry or concern. Now, it seems to be looked down upon. See this Psychology TodayPsychology Today article and the linked study for examples: https://www.psychologytoday.com/us/blog/meet-catch-and-keep/201806/why-people-dont-trust-couples-major-age-difference. When did this shift happen?