I don't think so. The newer generations are taller with proportional upper frames. Late teens and early 20s may appear to have smaller back, chest, less broad shoulders because they haven't build enough muscle yet. Plus their shoulders' width probably haven't reached max. Ossification of the clavicles doesn't occur until 25 for many and happens certainly after the long bones'
https://en.wikipedia.org/wiki/Ossification#Timetable_for_human_ossification
They are not.
Most.young guys are genetally very slim, tall and less masculine than previous generations.
A lot of hormones from foods make boys have more estrogens which make them taller but less built. It is really hillarious that nowadays most young men (25 and less) have almost the same arms as girls at their age.
Even if they work out, they have fit bodies but their muscles without roids are a joke. I see them everyday in my gym. On the other hand, the shorter ones (5.11 and less) most of the times are.much more built and manly.
So the men nowadays are taller but less masculine than before, thats for sure.
The same happens with many girls too, without plastics they have less curves than ever.
I believe that the next generations will have almost identical bodies the boys and the girls, with some small differences, nothing compared to the past were the men had broad shoulders and strong arms and women relatively big chest and ass (curves generally).
Thats why I don't care about tall young guys, because most of them look really bad and small even at 6.3.
Built young men with wide shoulders and strong arms at more than 5.11-6 ft are very very rare.