Libertarians are fringe.... Yeah, great, you've realized that Rand's followers are silly. Trumpeting it to everyone like you've had an epiphany quite possibly makes you even sillier.
I think "libertarian" is a large umbrella. Remember that Paul Ryan (who at least identifies as an objectivist) is the chairman of the House Budget Committee and was a major party vice presidential candidate last year. Of course, they lost, but the margin was way closer than it should've been if this ideology is at the fringe.
More pressingly, though, neoliberal dogma has reduced much of the economic discourse to "private sector good, public sector bad." That is, it's still very commonly believed that governments negatively distort markets (and that this is inherently and always bad), that public deficits (fiscally) crowd out private investment, and I'm sure there are still people who believe that public deficits are self-defeating because consumers will save the extra money to pay imagined increased future taxes.
So anyway, it may seem blindingly obvious (and a bit silly) to beat up on libertarianism, but by all accounts, people do in fact believe their bullshit. Maybe not under that particular banner, and maybe not in all ways, but neoliberalism is still the benchmark.