Vatican II ended in 1965, or 47 years ago (it started 50 years ago). Since it takes at least 7-9 years (after high school) to become a priest, the earliest someone could be ordained is at age 25. So, anyone who was ordained a priest during the years of Vatican II would be in his mid- to late 70’s by now. As of today, the average age of the 115 cardinal electors planning to enter the conclave is only 71 years, 10 months. Not sure that “most were ordained before V II”
I vaguely recall reading, 8 years ago, that Jospeh Ratzinger was one of only three cardinals of voting age who had been elevated to cardinal by Pope Paul VI (and one of those three did not participate in the 2005 conclave). This time around, all of the cardinals of voting age were appointed by either John Paul II (42%) or Benedict XVI (58%).