Speaking to the thread in general … I am far from an expert on Libertarianism. But it does seem to be a very broad church as others have said above. Which invites lots of No True Scotsman and “Is so! Is Not!” arguments. That way lies madness & failure to communicate, so about all we can say with any certainty is pretty high level summary stuff.
To me, this gets to the heart of it:
It is not a free life to constantly be ducking swinging fists that stop just short of one’s nose. Even honestly intentioned swings that somehow benefit the swinger. And that’s before we consider the swings of “Alpha” = asshole males who think it’s fun to watch people flinch. Or bad actors who actually want to threaten or actually hit people to get their way.
So as a practical result, we need to recast that aphorism as:
The freedom to swing your fist stops when/where somebody else flinches in response.
The obvious problem is the bright line of mutual skin-to-skin contact has suddenly become the fuzzy line of somebody else, the flincher/swingee, passing judgement on how close is too close about the actions of the swinger/flinchee. Real quickly after that recognition you recapitulate the history of human civilization starting from Hobbes’ State of Nature and end up about where we are today.
In a nutshell, IMO libertarianism is a philosophy that is easy to live by if you live on a large ranch waaay out in the country and ignore all the technology and value the the modern economy magically delivers to your front gate. You can swing freely because for all practical purposes, there are no nearby noses to hit or people to make flinch. Both physically and figuratively. Making a big polluting bonfire or toxic mining tailings or anything else like that with externalities just doesn’t matter when there simply aren’t enough people to make a dent in the Earth’s carrying capacity or even the local carrying capacity.
In suburbia or an urban area, or at work in a modern business, it’s all noses everywhere and you need to keep your elbows in at all times and your fists stowed. Failing that, violence and anarchy ensue or else there’s a vast police / regulatory presence to prevent the swings.
To be sure, there is a strain of Libertarianism that in effect assumes everyone will be “reasonable” and exercise voluntary restraint at an appropriate level so everyone will get along without government “help” in doing so. If only everyone is reasonable but also freedom-loving, enough, then all the coercive mechanisms of government can be shut down as unnecessary. Quite right. And if everyone was that reasonable, we’d not need Progressivism because we’d already be living there. Welcome to the Star Trek universe.
IME the Libertarians proposing this particular model are the ones quickest to heap scorn on the idea that human nature in bulk is good enough to embrace any Progressive idea. It’s all selfishness in those other people, but not me & my kind; we’re enlightened.
Backing up one or two meta-levels, I think a vast amount of the left/right cultural divide in the USA can be laid directly at the feet of population density and the amount of interaction with, and necessary consideration for, strangers and the inevitable side effects of one’s actions in everyday life.
Bottom line IMO: Libertarianism, and cultural RW-ery, though distinctly different philosophies, are both simple ideas suitable for governing only in a simple world of few people and small societies that may have existed a few centuries ago but certainly does not exist today at the national level of even tiny countries.