You're just using 'social hierarchy' as a buzzword.
Once you define what this "hierarchy" is and simply exclude arbitrary criteria from your definition because our subject at hand doesn't fulfill it at a specific point in history, you can come to your already predetermined conclusion.
Le Pen is in favor of socialist policies but only for "her people" and within a nationalist system, others are excluded. Therefore she's a right-wing national socialist.
H. H. Hoppe is a 'libertarian' but thinks political dissidents and homosexuals can be physically removed from society, therefore he's an extremist right-wing libertarian.
Hitler had a strong sense for collectivism and a volkskoerper within an Aryan ethnostate, therefore he's literally Hitler.
Pierre-Joseph Proudhon wants less coercion and exploitation in a society from which he wants to remove or potentially kill Jews and thinks poorly of homosexuals, women and other minorities, therefore he is ......
.... a leftist who attacks archaic social structures.
And yet you think a left-right scale is an appropriate model for looking at and understanding political philosophies in the historical context and allows to make clear assignments while looking at very complex and paradoxical (even within the parameters of their time) philosophers.
You can't pretend that a philosophy which would be classified as being 'leftist' today is some sort of successor of philosophies which were seen as or called 'leftist' after the French revolution if you admit that the criteria have massively changed. I mean you can but it doesn't say anything.
You simply ignore certain criteria which might be inconvenient for a simplified narrative and choose an arbitrary, very generic and self-defined criterion as the common denominator.
Social egalitarianism isn't the same as legal egalitarianism, isn't the same as economic egalitarianism.
It's not only not the same, people may have a philosophical foundation which makes them strongly promote one of those philosophies while totally rejecting another.
Your definition of 'fighting against social structures' isn't suitable to assess any movement, let alone right and left. Right-Libertarians also fight against social structures. Because progressive taxation, top rates, UHC in European countries etc are in fact part of social structures and they're enforced by an authority, they're not the state of nature. They go against the contemporary public opinion and the political structures. That doesn't make them leftists.
But it's not a 'development'. Classic liberalism advocated legal egalitarianism but not economic egalitarianism. Social Liberalism does. But that's not a development it forces you to answer fundamental philosophical questions about justice, rights, and society completely different.
"Right" and "Left" are simplistic terms, but they've
always meant support or opposition to existing social hierarchies in
every historical context they've been used in, bar one.
That one exception is American Right-Libertarians, who've decided to redefine it in terms of size of Government, with "right wing" meaning small government.
That's the conceit of your OP, not my argument about the definition, in which I've said precisely nothing about how meaningful the terms are in understanding political ideology.
Redefining terms like "liberal" and "left-wing" to support a political agenda certainly isn't advancing a meaningful understanding of ideology.
Social hierarchy is another simple term, referring to the stratification of income, existing wealth, social status and derived power.
Right-Wing Libertarians largely have no problem with that stratification, only the existence of Government and the role it might play in it. To the extent that some of them still support slavery.
Nozick said:
The comparable question about an individual is whether a free system will allow him to sell himself into slavery. I believe that it would. (Other writers disagree.) It also would allow him permanently to commit himself never to enter into such a transaction.
Contrast that with left-libertarians.
Murray Bookchin said:
My use of the word hierarchy in the subtitle of this work (The Ecology of Freedom: The Emergence and Dissolution of Hierarchy) is meant to be provocative. There is a strong theoretical need to contrast hierarchy with the more widespread use of the words class and State; careless use of these terms can produce a dangerous simplification of social reality. To use the words hierarchy, class, and State interchangeably, as many social theorists do, is insidious and obscurantist. This practice, in the name of a "classless" or "libertarian" society, could easily conceal the existence of hierarchical relationships and a hierarchical sensibility, both of which-even in the absence of economic exploitation or political coercion-would serve to perpetuate unfreedom.
Le Pen is much like Bismarck, in that her preference for a strong welfare state is secondary to her primary goal of ethnic nationalism, which is either a conservative or reactionary approach to the existing social hierarchy.
Hoppe is on the "extreme" of the right-wing, because rather than just trying to maintain the existing hierarchy, he actually wants an overwhelmingly reactionary return to the aristocracy of the past.
Proudhon's contribution to Anarchism on the other hand, is primarily about promoting the case of the worker at the expense of the capitalist in the context of class struggle.
He didn't just call himself a socialist as a meaningless label, he used it to refer to his attacks on personal property and wage labour (which not coincidentally read very similar to Marx in terms of capitalist exploitation of wage labour). His supporters were a large part of the First International. That's unmistakably a left-wing attack on the existing social hierarchy.
I never said that every left-wing or right-wing ideology shared the same path of intellectual development.
I pointed out that Marx was a bigot, and silent on misogyny, but Marxist Feminism is now a thing. The fact that left wing ideologies of egalitarianism have developed to include the opposition to racial, gender and sexuality based stratification doesn't mean that ideologies which don't include those dimensions are right wing.
With the quite obvious historical examples I've already given.
