The issue is identifying the actual medical issue, as documented by a doctor (doesn't have to be a real one
), which specifically entails that a passenger who is fit to fly (Y or otherwise) must be seated in a bulkhead Y seat because if not, it will create a significant functional impairment and seriously endanger that patient's life.
For QF staff (who have no medical qualifications) to "make the call" once boarded is completely absurd.
I am yet to be shown any documentation by those people here who are championing such a situation.
I forsee that those in support of the (as yet) imaginary medical condition being a valid reason for the above, will read this post and choose not to reply because they have nothing.
I actually am interested in seeing if such a condition exists for that matter.