Did we lose a smaller percentage of our population in WWII and that somehow goofs up our death rates which then somehow feeds bad data in to life expectancy bec

Did we lose a smaller percentage of our population in WWII and that somehow goofs up our death rates which then somehow feeds bad data in to life expectancy because the way they calculate it is off? I’m asking because this is the sort of thing which gets discovered all the time. Even, or especially, because it sounds so implausible.