while widely observed may not really be the case, I’d say that there is a general, very noticeable height gap between ppl under 25 and over 60 in Japan.
I live in Spain and the gap is also notable. I’m a short stocky 5’6” but I still stand taller than most ancient spaniards. The usual reason given is that they’re: 1. way hunched over and 2. they were shorter in average than the new generations (which stands at 5’8” average). Most obvious reason being: nutrition and lifestyle.
If you’re over 65 you’re more likely to have spent your youth in a rougher economy. Heck, Spain only got out of Franco’s dictatorship in ’75.
edit: spaniard abuelas are probably just under 5 feet tall. My asian female coworker who stands 5’2” is clearly taller. So yeah, they look kinda like smol ppl.