
Honestly... you cannot apply real world science to a land of magic.
Furthermore, I know quite a bit of people irl who only go up to the shoulder's of the opposite gender. Variation like that can only have a certain extent of demonstration in a game. In FFXIV (except for Lalafell) even the max height of a female of any race is only a couple inches at best taller than a minimum height of the male counterpart. It is a standard set by the artistic team. The Au Ra are a bit of an extreme example of this but still fall into the standard.
As for the physical traits differing from the rest of the races, there actually is less than people seem to think.
The head shape actually is quite similar to each other by what limited pictures we have. The female head is slightly more rounded which is more fitting for a shape of the body they have, while the male is slightly more oval to fit the taller build, but both come to a "point" at the chin. It is harder to see on the males because instead of facial hair they have the scales along their chin which gives them the rougher look everyone wishes the females had. Once again this is present in all races, females have rounder heads while men have more oval or square. If anything the Au Ra are closer together than others because their jaw shape is very similar.
The horns: They are different, no denying that, but what is the problem with having different horns for the sexes. Lots of games give gender specific traits, but as for the SIZE. If we were to shrink down the height of the male to the height of the female, I believe that the horns would be proportionally similar in size. However directionally they will be different.
The brow: Females have a softer brow than the males. That is once again an artistic standard for every race. While for some of them (elezen and Miqote) (excluding Lalafell because there is relatively zero difference between male and female in comparison to other races) you can give the male a very soft brow, as standard male of all races have a firmer brow.
The eyes: Eye style is very, very varied between options, but once again a standard of 'softer and more round eyes' exists for all females. THE EXCEPTION being Roegadyn where it is the inverse. Males have the rounder and somewhat softer eyes, while females have the piercing narrow eyes.
The Noses: Noses in general are weird and EXTREMELY varied between the options we see. If anything there is nigh zero dimorphism between the male and female pictured short of the size of height of the bridge of the nose, which is once again present on all races in character creator or not depending on the nose you pick.
Ears: I didn't see any ears on Au Ra... just horns.
Lip: Going through character creator, once again I noticed a trend: Pale lips for men that are 'flat' and pursed lips with color for women. Now I know you can change lips in the character creator to give men larger lips... but since we are going off 'standards' and the pictures we are given, the lips are actually less dimorphic than the rest of the races.
Poses: Yes the poses they provided seem to provide different personalities to the genders.
Builds: This is the only truly dimorphic aspect that does not fit perfectly into the present art style, or does it? Look at Roegadyn, Massive Hulking men, but in comparison slender females. In all races, (except Lalafell because zero difference) the females of this particular art style are always more slender and less broad. Even highlander females look petite compared to the male counterparts.
So... really the only thing extremely different is the Height and Horns. Likely the issue of dimorphic differences is because both females possess a pale complexion compared to the males of darker color, which gives the feeling of porcelain dolls. However, we all know better. The character creator has zero limitations between make and female skin tones.
Furthermore, I know quite a bit of people irl who only go up to the shoulder's of the opposite gender. Variation like that can only have a certain extent of demonstration in a game. In FFXIV (except for Lalafell) even the max height of a female of any race is only a couple inches at best taller than a minimum height of the male counterpart. It is a standard set by the artistic team. The Au Ra are a bit of an extreme example of this but still fall into the standard.
As for the physical traits differing from the rest of the races, there actually is less than people seem to think.
The head shape actually is quite similar to each other by what limited pictures we have. The female head is slightly more rounded which is more fitting for a shape of the body they have, while the male is slightly more oval to fit the taller build, but both come to a "point" at the chin. It is harder to see on the males because instead of facial hair they have the scales along their chin which gives them the rougher look everyone wishes the females had. Once again this is present in all races, females have rounder heads while men have more oval or square. If anything the Au Ra are closer together than others because their jaw shape is very similar.
The horns: They are different, no denying that, but what is the problem with having different horns for the sexes. Lots of games give gender specific traits, but as for the SIZE. If we were to shrink down the height of the male to the height of the female, I believe that the horns would be proportionally similar in size. However directionally they will be different.
The brow: Females have a softer brow than the males. That is once again an artistic standard for every race. While for some of them (elezen and Miqote) (excluding Lalafell because there is relatively zero difference between male and female in comparison to other races) you can give the male a very soft brow, as standard male of all races have a firmer brow.
The eyes: Eye style is very, very varied between options, but once again a standard of 'softer and more round eyes' exists for all females. THE EXCEPTION being Roegadyn where it is the inverse. Males have the rounder and somewhat softer eyes, while females have the piercing narrow eyes.
The Noses: Noses in general are weird and EXTREMELY varied between the options we see. If anything there is nigh zero dimorphism between the male and female pictured short of the size of height of the bridge of the nose, which is once again present on all races in character creator or not depending on the nose you pick.
Ears: I didn't see any ears on Au Ra... just horns.
Lip: Going through character creator, once again I noticed a trend: Pale lips for men that are 'flat' and pursed lips with color for women. Now I know you can change lips in the character creator to give men larger lips... but since we are going off 'standards' and the pictures we are given, the lips are actually less dimorphic than the rest of the races.
Poses: Yes the poses they provided seem to provide different personalities to the genders.
Builds: This is the only truly dimorphic aspect that does not fit perfectly into the present art style, or does it? Look at Roegadyn, Massive Hulking men, but in comparison slender females. In all races, (except Lalafell because zero difference) the females of this particular art style are always more slender and less broad. Even highlander females look petite compared to the male counterparts.
So... really the only thing extremely different is the Height and Horns. Likely the issue of dimorphic differences is because both females possess a pale complexion compared to the males of darker color, which gives the feeling of porcelain dolls. However, we all know better. The character creator has zero limitations between make and female skin tones.