This is partially explained by things like this:
During the past two centuries in the Netherlands, as well as in many more industrialised countries, a positive secular growth change has been observed.6 Various studies have shown that the positive secular change is mainly due to increase in leg length rather than in trunk length.1,4,10–13 Tanner reported that between the 1950s and 1980s Japanese height increased solely due to change in leg length. Sitting height showed no increase, so the trunk/leg proportions changed much more towards the proportions of North Europeans, though their final height was still 1 SD lower.14
Secular trend may explain part of the difference we observed between our study and the Oosterwolde study, a previous (regional) Dutch growth study including sitting height measurements and performed in 1980 and 1990.15 We found that our reference lines for SH for age and SH/H ratio for age were usually lower than the Oosterwolde study. Despite the fact that the Oosterwolde sample consisted of relatively tall children from the northern part of the Netherlands, the 1997 Dutch population was even taller. The Oosterwolde study showed that in 10 years (1980–90) the increase in height was more pronounced than the increase in sitting height, so the major secular change must have been in the legs.1
Source: Nationwide age references for sitting height, leg length, and sitting height/height ratio, and their diagnostic value for disproportionate growth disordersA.K.A. the Dutch study with the figures everyone here uses for sitting height and sitting height ratio.
If you aren't below a height threshold where your trunk is notably smaller than your usual man's, you can probably get away with lengthening your legs and still looking proportionate, as long as you keep your previously natural tibial/femoral ratio. Your arms may look short if your wingspan is lower than your height, but people like the Apo guy did humeri lengthening too.
With all that said, more than one (or even just one) operation is too expensive for most people, so many do super risky things like wanting to lengthen 9cm on a single segment with their doctors. Not even counting the risks/consequences of CLL itself - I'm casually talking about proportions here, but I never want to make these surgeries sound trivial. CLL is extreme; everyone reading this post here should be aware of that.