Sometimes even later. In local politics (from my POV) "this is how it's always been done" refers to something that had existed about 20 years when the boomers were born.
(So interwar.)
(The amount of critique in local politics we get for women keeping their own surnames or giving mother's surname to the kid is surprisingly high, considering the legistlation about giving father's surname to kid was only in the books from about 1920 - 1986.)
Might also be important to note that due to boomers being such a big generation (as the earlier ones were culled by wars, and the later by condoms) they've been the most important focus group for both politicians and media since early 1960s. Part of the "culture wars" is that the later generations collectively have finally gotten majority due to natural reasons.
(Related: why US presidential candidates' actions during Vietnam have been a major question for a quarter+ century.)