Again, not in my experience. I don't know which of our experiences is more common, but it'd be interesting to see some data. Though more focus on non-SpaceMarines can only be good for the hobby.
I can't speak for more female minis, since giant robots don't have genders generally, BUT my first interaction with Battletech wasn't about a conglomeration all-male posterboy factions that comprise fully half the game and have their own prequel game with even more All-Man Space Marines.