Well, plus King Arthur was a myth. And the tale therefore, is of a pie in the sky, "if only it were so" bent.
And even then, what happened? The main buddy, who liked to lance the ladies, a lot, put the cuckold horns on the King.
So much for equality, So much for chivalry.
That is the real story for adults, while kiddies, dream. Access to your wife means your best buddy needs killing. Very true today, even.
And as such, the most immature are taught it and other stories as a beginning primer into how fucked up the world is. Oh, at first it is make believe. Then we grow up a bit. But, now when I see Bugs Bunny, even, I see gag after gag of sex jokes and infidelities, and all the other adult stuff. Really those WB cartoons have quite a content.
All of the "fairy tales" are monstrous reminders that it is very dangerous world.
Ring around the Rosy
Pocket full of Posies
All fall Down (in the Scarlet Death)
But, we can't tell the childern, we are own worst and only monsters.
They find that out soon enough, right?