I agree that braids are not an impediment to service...depending on length, of course. I also agree that braids are predominantly used by African-American women.
As with any style, the real issue is field duty or combat duty. If anything imposes additional hygiene problems in the field, then it shouldn’t be allowed. Another field concern is whether it is more dangerous in combat...a handhold for an enemy. A long braid definitely would provide that.
Any such decision, then, based on hygiene or combat safety, should counter any concern based on race, religion, etc.
The Army does not exist to perform garrison duties. It exists to perform combat duties.
Most people don’t realize the consequence for a large majority of blacks who attempt to comply with these regulations ruling out cornrows or braiding. Attempting to ‘straighten’ the African American curly hair is far less natural and time consuming than keeping it short in either cornrows or short braids.
It additionally requires extensive chemical treatment with risks of going bald in either case.
For black women in the military, the cornrows or short braids is an appropriate military hair style. For black men, the cornrows also is appropriate, just as appropriate as a flat top or a burr haircut.
To regulate out these styles is equivalent to mandating all military men must have micro curly hair, which would take white males an equally long and artificial effort to achieve in order to comply with such a regulation.
IMHO, too many regulators confuse those who seek these methods as being rebellious to grooming standards, but fail to understand or simply ignore the racial differences which effect the methods of grooming and field hygiene.