If the definition of patriarchy were one of how social mores are crafted within society, anarchists do have some feeling on it. It plays a role in the social order and is part of the domination of daily life. The relationships of institutions to families, to individuals, to socio-economic conditions ends up playing out in a way where societal norms favor the male as a dominant gender.
To "smash patriarchy" or find ways to overthrow the domination of heteronormative mores ends up being another vague concept in the teleology myth that anarchists believe they are often working towards. Like all myths, there is little value to a strategy to defeat such things, but an analysis of power from other genders tends to expose society's favoritism of males. There is no way to separate patriarchy and somehow turn the tide towards the domination of another gender, even from a Marxist-Leninist or Fascist point of view, should they take up a practice of attacking what is perceived as enforcing patriarchy.
An analysis of what anarchy could be would be a negation of present social mores which could lead to some re-balance of power where what is seen as favoritism is no longer a major aspect. Should patriarchy not end, there would not be an end to domination as social structures would continue to enforce gender bias and social castes where males come out ahead regardless of individual merit. Thus patriarchy could not be a part of anarchy and/or what could be called anarchy fails to end domination, making it worthy of a critique of power from anarchists.
Just as a primitivist could claim an industrial society is not anarchy or the kind of anarchy that answers their critique of society, so too could an anarchist with a critique of patriarchy claim the same should patriarchy be seen as an existent force.
Why males always come out on top throughout history is either an obvious and simple answer, based on the tendency of males to hold the threat of physical violence on their side or more complex based on a division of labor created despite the physical presence of males. Women can hold physical power, agility, knowledge, cunning, wit and so on, just as any individual can.
The division of labor from the dawn of civilization specialized "men" and gave them the social caste where they hold more sway on the use of violence in society, even when they hold traits sometimes considered weak within present society. The lack of flexibility with this social caste essentialized the roles of men and women, leading to a society less defined by what you do is what you do towards what you do is because you are from a particular gender.
In some ways, a meritocracy leads to patriarchy over time due to what is considered of merit in society and what isn't. More fixed roles in society came with the advent of property because determining ownership and inheritance needed a framework to not confuse who got what after the family leader died. While a family would believe they knew best, when a dispute would arise, what has become known as a state would have to judge ownership and enforce ownership in a way that was considered "fair".
By the time property had begun its origin, men had already fell within a division of labor where they often were hunters, warriors, herders, field workers...taking on physically demanding roles while women were already lead down the path of being central to child rearing, food preparation and menial tasks that are today considered less important and perhaps were defined as such then.
It would be wrong to say this was absolute, but because the division of labor had created a social caste favoring men as a force of violence above women, men were also the social caste that created a territory's monopoly of violence, the state. So property laws were more often settled in a "fair" way which favored male inheritance as a way of determining who got what property, further reinforcing the social caste of males as patriarchs, despite a lack of merit they may or may not hold as a family leader.
This isn't to say de facto power wasn't the real power, but if we look at today's laws of incorporation, which have the "benefit" of being written, someone is still held primarily responsible for the corporation. Laws of the family still hold children as property, though because of the division of labor, women are more often given children due to their perception as the gender that raises children.
My answer is incomplete and speaks little of the many exceptions to the rule on how civilizations were defined and founded, but I feel, from what I've read, that it explains the division of power and why the social order tends to favor men over women, even when men aren't ideal as what men are perceived to be.