Juan, I'm still waiting for you to justify your claim that Christopher Cantwell isn't a libertarian. Your merely pointing to his assertion that libertarians shouldn't be (or need not be) in favor of open borders, simply highlights which side of the argument you are on: It doesn't say that Cantwell is necessarily wrong. It would help your position immensely if you could point to a substantial number of positions Cantwell has taken which libertarians would generally agree that contradict libertarian philosophy.

I suggest you read https://christophercantwell.com/2015/12/06/why-libertarians-are-hopeless/ which I include a segment of, below. I suspect you are exactly the kind of problem that Cantwell is referring to: People of the left who are simply pretending to be "libertarian".

Jim Bell

[partial quote below]

Why Libertarians Are Corrupted By The Left

I should again explain, I am discussing libertarians, not libertarianism. The following critique would rightly be met with complaints by well read Rothbardians as containing a great many falsehoods. I have made these complaints repeatedly myself.

In their efforts to grow their numbers, and in the face of perpetual frustrations in getting wolves and rabbits to shrug off their evolutionary psychology, libertarian groups have resorted to recruiting non-libertarians into their ranks. This presumably was perceived as a competitive advantage in a political system which favors numbers over reasoned arguments or factual correctness.

In the course of so doing, it is my perception that leftists are particularly more prone to swing toward libertarian social circles than rightists, due primarily to a lack of ingroup preference. It is not that they become libertarians or suddenly shrug off their rodent like evolutionary psychology. They are simply more prone to novelty seeking ,and lack any group loyalty or attachment to any particular idea. They are still rodents, but they realize they can have a higher social status in this smaller group than in their larger openly left wing group. A left libertarian blogger may become the envy of his left libertarian peers, but would accomplish absolutely nothing when competing against the vast expanse of mainstream liberal media.

The rightist on the other hand is less prone to novelty seeking, has a higher ingroup preference, and is more averse to radical changes in the existing social and economic order. Additionally, he is aware that his inferior numbers make his absence in a democratic contest far more consequential than that of the leftist. So he is far more averse to radically altering his thinking, his social circles, or his political activity to favor a more libertarian order.

Thus, while libertarianism as a well thought out philosophy would be more appealing to the rightist than the leftist, the leftist gains undue influence in the libertarian social and political scene. That leftist influence dilutes the body of thought as left tainted media is produced and distracts from the writings of the Rothbards and Hoppes of the world....