As an early boomer (1949) we always had dinner at about 5:30. Both of my parents worked.
As a Gen Xer (66) we ALWAYS at at 5-5:30, and my 86 year old mom STILL does. Not because she’s 86, but because that’s the time that you eat.
My Mom always had dinner on the table at 6:00PM sharp because that’s when my Dad liked to eat. He got home around 5:30 and we sat down at 6:00.