Go into any used bike store and you'll find nothing but mixtes. They are slow sellers, and plentiful. There definitely is still something of a chauvinistic attitude towards them. And women cyclists on average are still less plentiful than men, and they too sometimes choose a "men's" bike too. Most men still refuse to ride a mixte even today.
It's too bad, because mixtes are often a great deal. I've eyed a few cool looking ones in the past but never got around to buying one because of budget.
Hmm, not around here! Mixtes go pretty fast in our bike shops. I see a few here and there but they sell out! I see men with them often! One of my friends is a daily rider and he rides a blue mite - and wears a suit a lot of the time.
That being said, I have seen quite a few men sporting mixtes. It isn't 50/50, but it might be 70/30 women/men around here.