Times change and not all people are the same. A racist libertarian from the 1960s in no way represents a libertarian in 2023.
The statement that "Racism seems to be part of libertarianism’s appeal to some Americans." is completely unfounded and even if it is true for a certain percentage, you can't make that general claim. We should note that anyone willing to make those kinds of generalizations are probably themselves suseptible to being racist.