The word libertarianism originally referred to a socialist school of thought[0].

> Traditionally, libertarianism was a term for a form of left-wing politics; such left-libertarian ideologies seek to abolish capitalism and private ownership of the means of production, or else to restrict their purview or effects, in favor of common or cooperative ownership and management, viewing private property as a barrier to freedom and liberty. In the United States, modern right-libertarian ideologies, such as minarchism and anarcho-capitalism, co-opted the term in the mid-20th century to instead advocate laissez-faire capitalism and strong private property rights, such as in land, infrastructure, and natural resources.

[0] https://en.wikipedia.org/wiki/Libertarianism

You have a very narrow understanding of socialism then, there are many different forms of social ownership. State owned is only one of them.