Yes, lets impose a "sense of realism" on a game and system where things like a score of 18 (or even higher) can be achieved and you can be more physically strong/agile/durable/intelligent/wizened/persuasive than most any other member of your species by a long shot.
Even as any sort of "realism" those house rules make no sense, and that is including everything - regardless if the game was toned down to actual medieval levels and had a lot of concepts rebuilt around reality - and I do mean everything. I could realistically see someone who was doing a very "down to earth" medieval game that women would have non-statistic related penalties (as would most everything else in the world, mind you) and issues crop up roleplaying wise, but even then... Really?
Especially for the heroes (or villains, if appropriate), just why? Isn't the point of being a hero - in part - to be more than everyone else, or else everyone would be heroes?
What about other species? Most likely this is ruled out in a medieval campaign (you're all playing humans most likely), but even then, it begs the questions about monsters, unless there are none.
Why specifically stop at 16? That's still pretty arbitrary. Just so even if they would have had an 18 in a score (if they were a male) you can ensure they're still inferior by that little bit? If you're going to go that far with arbitrary rules, why stop there?
If there's magic in the world and that's acceptable (or even acknowledged) in your "realism" how is that less foreign or impossible to believe/understand/rationalize than a woman being superhumanly strong? Why can't she even just result to the "a Wizard did it" excuse to explain why she's stronger than 90% the party or something absurd? (Again, even then, that's still a crazy excuse - she shouldn't have to do that just to play a character of her gender, or in the case of a male, play his character of an opposite gender.)
Too many questions - no answers to any of them that I like.
Just a bad, bad sign as mentioned previously by others.