I would comply for as long as it took to move around the next corner, and then resume my more cool posture. As we get older it becomes more and more important to be attentive to our posture.
Age causes some changes in the discs that separate our spine vertebrae.
We lose a little height as these discs become a bit thinner with age. This causes other soft tissues like ligaments and muscle to become a little less tense than when we were younger. This slight reduction in tension can cause an increase in that rounded over posture we get. So it is even more important as we age that we be attentive to sitting and standing tall. Strengthening the muscles that squeeze the shoulder blades together is very important in reducing round-shouldered posture.