Also found out that one of Yoshizawa's descendants,
Atsushi Ogata, is a modern movie director.
Son of
Sadako Ogata, academic, diplomat, and former United Nations High Commissioner for Refugees (UNHCR), among other positions, and her husband,
Taketora Ogata, who's the son of a former executive director of the Bank of Japan, and was the former vice-president of the Asahi Shimbun newspaper himself.
So definitely not someone who'd have had a problem with nutrition or healthcare. He looks about the modern Japanese average of 170~173cm.
There's nothing much that could be taken from this post, as he is still a few generations behind the most of the posters here, but the study I analyzed in the OP did mention "The impressive rise in height in Japan stopped in people born after the early 1960s (
Figure 6)". So, I think, with ideal healthcare and nutrition, and assuming men and women won't choose to only have children, on average, with the tallest among their peers that they can 'get', average height levels should remain rather flat in developed, homogeneous, first-world nations - given a well-off, normal family. The height discrepancy among men and women didn't change in 100 years, despite the total gains in height, after all. Unless a strong sxxual selection starts happening for height in both sxxes, I think the nutritional and health gains have to hit a cap, on an average level for the population. Thus, the flattening of the rise in height.