If you ask most fitness people they will tell you that flexibility is an important component of being 'fit'. They will emphasize the benefits of becoming more flexible and the value of performing flexibility exercises like yoga. Of course, most of these people are very flexible to begin with, and mostly female. They can get into poses like the one above.
On the opposite end of the spectrum, very muscular individuals (such as male bodybuilders), tend to place a lot of emphasize on strength training and tend to ignore flexibility. These people tend to have stereotypical postures- internally rotated arms, puffed out chest. They can't reach above their head and definitely can't get into the above pose.
So, who is correct? The extremely flexible yogi or the very muscular bodybuilder. Well, the answer is neither. They are both missing the point. Flexibility is not a more-is-better quality. In fact, flexibility should be viewed joint-by-joint and should be looked at in terms of optimal joint alignment. You can have too much flexibility in a joint, which leads to too much joint motion and joint instability.
So, the correct approach is to assess each joint's motion and correct its function with the combination of stretching tight muscles, activating weak muscles, and shortening lengthened muscles with strength training. Each muscle's length and strength change in response to your daily movements or postures. An indiscriminate approach to stretching may be counter-productive and lead to more joint instability.
Hopefully, more 'fitness people' understand that flexibility training is important and necessary, but must be used in context of optimal joint function. Balance is key. You may need to stretch certain muscles regularly and not stretch, but strengthen other muscles regularly.
It comes down to optimal functioning. Check out the video below. She appears to have good hip, knee, and ankle flexibility, but she also has good strength in those joints to keep them stable (and prevent misalignment and pain) with movement.