Earlier quoted context omitted.
high time preference thinking
Only gotta last 80 years, it's pretty rational given the constraints. The what-ifs are unlikely to materialize at all, low probability to happen to you, and avoiding them if they do materialize requires that neither you nor any of your relatives submit their dna or have any contact with the justice system ever. DNA is already protected from use by insurance companies so that's a future harm that already got squashed.
And their murderers mostly only had census data and people willing to snitch on their neighbors to go on. A DNA database? Oof.