Right, it was a very limited study only affected the soleus which is a slow twitch muscle compared to the gastroc which is fast twitch. What I would do if I were them is track the calf development of beginner ballet dancers to see if they are held back by genetics or not. My bet is that they would be surprised to find that even the skinniest would have statistically significant gains over time. Higher reps and constant use are the way to engage the inner calves.
Regardless, I think calves probably offer the least joy in terms of exercise response as compared to just about every other muscle group unless you're born with a good amount of muscle fiber in the area. But then they were probably impressive to begin with.