Well, libertarian doesn't necessarily mean someone in line with the Libertarian Party of the US. If we want to consider the meanings of these terms by referring to how they are understood to in the US, we would be all very confused, since everything in the US seems to have a twisted meaning.

See for example, their Fascist party is called the "Republican Party"… Their Right-center oriented party is often referred to as a "left-leaning" party… and finally there's another right-wing party with slightly different positions than the fascist party, calling themselves the "Libertarian Party", because why not! 🤷