If you defend gender limits on Strength in a game because of "the basic facts of anatomy," are you going far enough?
Most research studies put men on average at about twice the physical upper-body strength of women, whether measured by lifting or throwing (even this meta-analysis challenging the importance of psychological sex differences has to acknowledge the strong physical sex differences on this score.) To put it statistically, effect size differences on things related to the Strength stat in roleplaying games range from 1.5 to 3 standard deviation units (d). The distribution overlap for a d of 2 looks like this:
What this would mean is that 2.5% of women are physically stronger than the average man, and 2.5% of men are less strong than the average woman. If you assume that the male is the norm for the D&D character (and given the premises of this discussion, hey, why not?), this translates to a -6 penalty to female Strength, so that the top 2.5th percentile cutoff of the female distribution (3d6 roll of 17+) matches the top 50th percentile cutoff of the male one (3d6 roll of 11+).
Nothing this size exists for psychological differences, so unless you're positing some very bizarre cultural constraints, balancing out male strength by giving women characters a +6 to "wisdom" or "charisma" or what have you is just as unrealistic.
And people are arguing about AD&D capping human females at 18/50 strength? It's clear that neither realism nor equality are served by the classic rule, which can only be defended on the grounds of tradition.
My own game's rationale for not having gender modify strength: Along with the wizard, the dwarf, the elf, the barbarian - each of which rests to some extent on a suspension of disbelief - there is another fantasy archetype, the "warrior maid" or "kick-ass woman." Whether her name is Penthesilia, Bradamante, Wonder Woman, or Xena, both men and women love to watch her, and sometimes to play in her role. Anything the system does to make this character possible, and attractive to play, is allowable.
Long story short: why the hell are people so concerned about female anatomical realism when half the female fighters in D&D art look like this:
And if so, why can't they equally "unrealistically" look like this?