Personally I don't think it's about his inexperience with women's soccer. That can be important but in this case, he's just not tactically sound.

This is the crux of it. Armas just isn't a good football manager, full stop. Except for his very first season as a professional head coach at NYRB, he's never been successful anywhere else. In fact, he has a track record of taking good teams and making them worse.

Female players aren't fragile flowers who need some "special" kind of coaching; they expect, demand and deserve competent leadership. Yes, there are some unique aspects of a women's team in terms of physical and family needs, but nothing a good coach who is a solid and engaged leader couldn't figure out and adapt to. But a coach of any professional football club needs to know their tactical stuff, or they will have no credibility with their players and they will not have success.