In Victorian England, why were women considered to be below men if their ruler was a woman?

In Victorian Britain, and indeed in Western Europe going very far back indeed, patriarchy was one of the dominant organizations of society and culture. There were a series of laws that varied from place to place and over time, but that none the less gave greater legal status to men. These included but were not limited to the following: they could own property, pass along inheritance, gained legal control over their wives' property, control the destiny of their children, take active part in politics as officials at local or realm-wide levels, serve in higher and more powerful positions in the church, engage in business, and on and on. Patriarchy also operated on a cultural level, so that positive values were often associated with males: strength, loyalty, reason, piety, and so on. Men were assigned privileged and/or more rewarding tasks in society, such as going on military campaigns, long-distance trade, and market labor, while women were systematically confined to the home, denied access to the most rewarding opportunities, and restricted to activities that were devalued or non-monetary.

(Before one replies with, "Yeah, that makes sense; dudes are stronger, and women should stay home with the kids!" keep in mind that (a) these kinds of organizations are not universal, (b) not necessary, and (c) not static. Unlike our needs to eat, sleep, or (on a social level) fuck, the roles and power assigned to the different genders are very changeable over time. And, if they're changeable, that means they are not the product of "natural" roles but are in fact the result of human choices and power relationships.)

Anyhow, this is the deep social and cultural context we're dealing with in 19th c. Britain. Within this system of patriarchy, it was possible for women to "slip through cracks" and attain positions of power, and that did not necessarily mean that they challenged the overall patriarchal order. So, in some cases, women whose fathers had died, who either had no sons or whose sons were minors, and whose husbands died, could in fact become the legal holder of property although they might not be able to otherwise. In other cases, a woman might end up being the only legitimate (and politically acceptable) heir to a throne, despite the fact that kingship was a "male" domain.

So, understand that Victorian Britain was a deeply patriarchal society. Women were considered to be broadly irrational, weak, emotional, not suited to the market or politics, and best geared only to make babies. Women who deviated from these norms, such as working-class women who nearly always had to work in order to help their families, were stigmatized by the middle- and upper-class Britons who dominated society and set its cultural values. The early Victorian period, in fact, was the moment at which we see the emergence of the idea of a "breadwinner" wage. Early industrial labor in the late 18th century often employed women and children to handle machinery, and in some cases working class families were moving toward egalitarian relationships. But, when working class Britons argued that they should be included in the realm of expanded political rights along with the middle class, the middle class argued that working class women worked and that their families were therefore morally suspect. In response, working class leaders essentially said, "Well, if you want our wives to stay home, you must pay working fathers more"--hence, the "breadwinner" wage. (See Anna Clark, The Struggle for the Breeches).

This level of patriarchy cannot be undone simply by having a queen, especially when the monarch was relatively powerless; Victorian monarchs were not expected, for example, to lead their knights on campaigns each year, as medieval monarchs were. Further, there was no shortage of other royals and noblemen to take up the more masculine aspects of kingship for which Victoria was unsuited.