“The psychologic impact of an anterior chest wall deformity, or pectus deformity, on the patient can be truly devastating.”(Ellis)

“In the popular mind the size and contour of the thorax is associated with virility in the male, beauty in the female, and sex appeal in both, so it is not surprising that persons with chest deformities avoid clothing and activities that make these deformities noticeable.”(Lester).

For this reason you may have not seen people with pectus excavatum / sunken chest yet.