Sounds like optometry here is administering the required tests for a FCIII wrong.
Unlikely. Many lack sufficient familiarity with the examination to have awareness of the tests being administered to understand what is being looked for and more importantly why.
The Air Force in selecting applicant for a job or to perform duties of a job has the obligation to ensure the individual has the functioning ability (mechanical, physical, and biochemical functions of good and/or normal health) to do tasks safely.
The aircrew flyer class medical examination vision standards exist as result of visual demand of performing the crew member tasks of flying an aircraft.
Pararescue, CCT and similar jobs (duties of AFSC) also have tasks performance placing significant different visual demand concerns of operational environment through a continuum of brightest day and darkest night. Less than normal vision does increase confusion when performing visual tasks. Less than normal vision can influence having abnormal body posture and balance problems among other problems.
For example a person can have perfect 20/20 acuity, but the person's ability to see objects against low contrasting backgrounds is impaired. Some common Contrast Sensitivity degradation examples are night blindness and extreme light sensitivity. The point being is the MEPS and subsequent Class III aircrew exam is looking at many more aspects of normal vision than the typical civilian eye exam.
The second point being made is the vision standards are of such amount of what is qualifying and what is disqualifying that it is impossible to rely on what is posted here as what actually caused the disqualification. The pointing out the test you were referring to was testing something else other than depth perception was illustrating the lack of reliability of what somebody thinks the test tests and what it actually tests exists.