Well, that’s the rub. Galt’s Gulch might look appealing to some as an ideological principle, but when you read about it in the book, it came across as a bunch of ideologues rigidly upholding libertarian principles, and they’d rather let another denizen die rather than break them.
There is a thing called a civil society that people ought to be able to agree on, that in a nation with X amount of wealth and resources, a set of “Y’s” should not be allowed to occur. Starvation of children. The mentally ill having no recourse but to live on the streets. Etc.
Reasonable people can debate what the components of that civil society are, and the means by which we collectively achieve them. The term “collectively” is not incompatible with libertarianism; it just acknowledges that no governmental ideology can exist in its purest form.