I'm guessing there's some sexist or something going on...who knows. Maybe the writer thought that when a person pulls the sword from the stone they become King...not Queen, so who knows. As for the picture I really like the decal on Saber's shirt. Its quite funny actually.
She is a king. But in fate stay night shes arthuria pendragon. Shes a woman disgused as a man since no one would take a female leader seriously. I think it mentions that in the game somewhere lol
The real answer is: Takeuchi REALLY wanted to draw a woman in armor, combined with the reality that they'd have to make an entirely new audience to play a game with a woman protaganist convinced Naasu to write saber as a woman.
Actually in the original idea Saber was a male with Archer-like personality: post #459507 And his Master, the main heroine a glasses-girl mage. post #220735 Though I am uncertain how much she resembled Rin. Anyways as FSN became a VN and and so an eroge it was natural to switch the genders...and actually many other things. You can't imagine how many weird ideas they had. Actually even I can't.:)