Bahahaha. QB's have to have really strong arms. And they generally have to be tall enough to see over their linemen. Also, do you really think a woman would be more durable than a man? They get hit. A lot. Anywhere and everwhere. Have you ever watched football?
The ability to throw a football is more mechanics than sheer strength. Also, not every QB out there has the long ball ability of Brett Favre. There are many that are short distance throwers that still start.
As far as height goes, there are many QB's that are in the 6'0 - 6'2 range, by no means "tall"...for a woman yes, but look at the rosters for the WNBA and the olympic volley ball teams...there are some very tall female athletes out there. Obviously the "ideal" height is probably around 6'4"-6'5", but there are many exceptions.
Concerning durability, I think you underestimate how tough some women can be.
I watch college football every Saturday and the NFL every Sunday. The NFL is an elite crop of male athletes.
Have you ever watched any elite female athletes compete? Women can be taller, stronger, faster, and tougher than you give them credit for.