One major way in which to look at this question is through the lens of social mobility. One may compare the society of Huxley's book with modern American society (and with how much American society lives up to its ideals).
In the book, class is a physical characteristic. A person is "born" to his or her status and can have no other status (unless there is something wrong with the person as is the case with Bernard). A person cannot become significantly richer and cannot move to a significantly different station in life. There is no real social or economic mobility in this society.
In modern America, success is defined largely by what one makes of oneself. We assert that there is social and economic mobility in our society and that those who remain poorer have failed while the "haves" have succeeded by their own efforts.
But one may ask whether the United States really does have that much social mobility or whether it is really like the society in the book where some people are born and conditioned to hold a certain, unchanging place in their society and economy.