The difference between our family photos and others is that the photographers always stood way way way back to get everybody in both vertically and horizontally.
The result was a tremendous savings in the cost of photos ~ which is why we have some of the big guys.
Never fear there were always large people around ~ even going back into the 13 and 1400s ~ the Iroquois warrior elite was typically 7 ft tall!
Some people from Polynesian islands are genetically programmed to be huge, which is partly why there are so many Samoans in the NFL. Pima and Papago Indians tend to be obese, because their ancestors were adapted to a harsh desert environment where starvation was a constant threat. However, the prevalence of obesity in today’s American population is unprecedented. I look at photos of Americans from a few generations ago and see people who mostly look downright skinny by modern standards. I remember as a child that most of my colleagues were not fat. We went everywhere on foot or on bicycles. We were not ferried to “youth activities” in minivans equipped with cupholders, the better to carry high-fructose soft drinks.