Why has Ayn Rand become so inconsequential to modern philosophy? The point is underscored by the lack of any references to Rand on your site, save one instance where someone asked if there were any refutations of Rand's Objectivism available – to which a link was dutifully supplied. The point is further underscored by some questions in regards to women in philosophy (or the lack thereof) which, to my amazement, Rand was not referred to (even begrudgingly) as a positive example. My pet theories about this situation have something to do with her aligning herself strongly with Capitalism, while philosophers historically have been left leaners or overtly aristocratic (of sorts) but never very money orientated, which is probably seen as a very Earthly consideration to dwell on. Some say that Rands format of conveying philosophical ideas in the form of novels has not helped her cause much. If this consideration is to be given weight then why should Socratic dialog, for example, be so revered? The methodology of presenting a dissenting opinion in Plato's Republic is rendered null when that very opinion is not only authored by the same person as the opposing view, but can only be interpreted as being rather strawmanish anyway. I'm not trying to diminish Plato's works – they are brilliant, I'm criticizing the assumptions that may have effected Rand's popularity unfairly.

I don't think Rand's alignment with Capitalism has much to do with her lack of influence on modern philosophy. It's true, to be sure, that the majority of philosophers nowadays tend to be left-of-center, but there are plenty that are not. To give but one example from recent philosophy, Robert Nozick's Anarchy, State, and Utopia could hardly be described as leftist, but it is an acknowledged classic nonetheless. Similarly, Rand's presentation of her ideas in novels isn't unique. There are writings of Nietzsche's that are in much the same form, and he's still taken seriously.

I'm afraid the reason Rand is "so inconsequential to modern philosophy" is rather less interesting: The overwhelming majority of contemporary philosophers find her work to be of poor quality.

I agree with Richard Heck on this one. Rand's view of the human person, of freedom, of perception, of markets, etc., seem to me and to most philosophers I've spoken too about it, unpersuasive, overly simplistic, and sometimes objectionable. But I would add two bits:

First, I have encountered a few philosophers of quality who respect Rand.

Second, I suspect that there are reasons besides the quality of her thought that contribute to her being relatively unpopular among professional philosophers. Among those reasons I'd include: (a) that like Voltaire Rand is more of a popularizer than an original philosopher; (b) that she worked outside the academy and the professional institutions of philosophy; that much of her work appears in rhetorical forms atypical of profesional philosophy (e.g. fiction); and (d) that her philosophy seems excessively driven by her politics. It's also interesting to consider whether her sex may have been a factor in her not being taken terribly seriously. One might compare her to Weil in this regard.

Read another response by Richard Heck, Peter S. Fosl
Read another response about Philosophers