We've already answered this 5 pages ago.
BC they were kids, BC more than likely they just didn't think about it, or just didn't care. A passive stance that most of them probably regret now, but just didn't have the worldview or maturity or enough meaningful interactions with african-americans to appreciate the implications of their actions in 1980. It's certainly fair in 2019 to ask 'why did you do that?' or 'what is your stance on the flag now?' and then listen to their explanation.
Just like if we went back and looked at 19 year old PH in the yearbook, posing outside the sociology building in a black Green Lantern Tee, Zubaz pants, clunky horn rimmed glasses, and Karl Malone LA Gear hightops, we might ask....'Were you an giant dork then?' or 'Did no one ever teach you how to dress?' or 'Did you have any friends that were not virgins?' and then we might then follow up with questions on how you've changed like 'Have you learned how to dress like an adult?' or 'Do you let your wife purchase and pick out your clothes now?'