Besides collapsed arches, Kelly Starrett has written multiple books on basically moving properly, including this classic hip hinge. I sort of became obsessed with his mobility teachings for a year or so after reading his "Deskbound" book (https://www.mobilitywod.com/deskbound/). Part of the problem is that we sit all day, and sitting in chairs is so ingrained in our culture. At some point we forget how to move properly, and our body begins to adapt to the awkward positions it's forced to sustain for hours on end every day. We develop scar tissue in key areas in order to strengthen and lock our spines/shoulders/hips in place in the bent over sitting position, such that when we do normal human movement tasks our primary muscular movement systems are out of commission due to lack of mobility. So our secondary and tertiary muscular movement systems need to be used instead, like our lower and mid-back muscles for bending over. But these are weaker and were never meant for long term repeated use. So we end up hunching over with terrible back pain all of our lives. The classic hunchback old person who's a full foot shorter than he was 40 years ago that we see here all the time is not a thing in places where people are physically active their whole lives and squat or sit on the floor instead of sit in chairs.