You're missing the point of what assertiveness is. It's about creating opportunity, not sitting on your ass and waiting for the world to cater to your needs. Life is what you make it and one has nobody to blame but themselves for where they go. True, we don't choose the starting point, but we do choose the destination.
> you'll always stand on the side-lines and will forever be relegated to being a spectator.
Yeah, if the men are allowed to be in charge.
I think that a distinction must be drawn between being assertive and being abusive. Assertiveness is, in my opinion, nudging your way forward and reacting to people's objections by talking to them then taking their opinions into account and, if they lack assertiveness, representing their opinions. If someone else is also fighting for that spot, team up with them and work together.
In contrast, abusiveness is nudging your way forward at the expense of peoples' well-being and not respecting others' right to assert themselves.
In other words, it's the difference between fighting for yourself and fighting for everyone including yourself.