This is true.
The point of voting libertarian at this stage isn't even the candidates themselves, it's about having more choices in the long run. Today, a tiny party like the libertarians just doesn't attract more qualified/capable candidates because they can't offer them what the big parties can in terms of money, visibility, and the chance to actually, you know, win. This will change if the party gets more viable through funding, visibility and support, and this will mean changes for the party, too.
Right now the 2-party system has a stranglehold on American politics, and that has to be broken.