Braznor or any other Hindu has every right to opine on the caste system's effects as they see it. The only issue is when one implies that the purpose of the caste system was to keep people down in society.
The fundamental difference in Hindu philosophy is that although the soul, known as
AtmAn is non-different from
paramAtman (Brahman), the "clouded" soul, or
jIvAtman which determines incarnation (birth), are indeed different. This is no excuse to abuse anyone. However, one must recognize that all incarnations are NOT equal! Different people, animals, even inanimate objects have their purpose and strengths.
This oft-repeated nonsense that "all is same" is a recipe for disaster. Just because the mouth and the anus are both orifices does not mean one can eat through either of them. They both have their own purpose.
Of course, as Braznor has stated, one must definitely have the freedom to choose what field they want to study and become a professional in. Caste system has nothing to do with that. The abuse of the system has kept people pigeon-holed into professions they had neither aptitude for nor interest in.
As I've explained before in another post, VARNA is the inner quality while JATI refers to birth-based vocation. The two cannot be used interchangeably and thus the caste system is not at all rigid as it is erroneously assumed to be and as it has become over the past couple of centuries. Jati somewhat affects the Varna and thus the "caste" of one person became rigid over time. It is hard to be passionate and successful in astrophysics when one has been brought up by farmers. Of course, it's not impossible, but the chances of that person (farmer) becoming a successful astrophysicist is quite small. Someone from an academic household or household of scientists is much more likely to take that path. The same is applied when it comes to study of the Scriptures. One is much more likely to pursue the study of the nature of reality when one has been brought up in that surrounding.
In ancient India, when the traditional education system was prevalent (gurukula), students learned the various subjects such as academic inquiry ranging from mathematics, astronomy, and medicine, as well as learning practical disciplines such as warfare, statecraft, archery, wrestling etc. Combined with this was the study of the Scriptures (Vedas) which included Yoga, dhyAnA (meditation) etc. According to Hindu scripture, only those who are twice-born (
dvIjA) should be allowed to learn the Vedas. Since the twice-born are comprised of the three castes of Brahmins, Kshatriyas, and Vaisyas, Hindu society was at the zenith of the world in all aspects. The Sudras or laborers were mainly trained in vocational disciplines from within their families.
A holistic system that includes practicals, theory, and application are fundamental to
experiencing that which we learn. The Hindu system of gurukula was exactly this. It was no surprise that since Brahmins were always in the field of scholarship and research, they excelled even in the secular education imposed by the British after they rendered the gurukula system untenable.
In fact, nobody is kept out of getting a good education today. What is really surprising is that India has implemented an affirmative action type scheme of its own, just infinitely worse than the affirmative action found in the US. A student from a "low" caste family needs to score only nominally in the entrance exams to get admission; whereas, a Brahmin, no matter how poor he may be, can't even think of getting admission to the really sought after disciplines such as medicine, engineering, and other sciences unless he scores above 95%. IITs, being the sole exception of a government run institution, has maintained its meritocratic policy and is dominated by Brahmins both in professorship and scholarship (students). It is because of this "reservation" policy, as its known, many brilliant Indians emigrated to the west in the 1960s and 1970s. India, keeping talent down, is only now realizing that merely sidelining people for the sake of votes is not helpful. This reservation policy is the worst form of caste based abuse ever. Instead of taking a student's economic and educational background into consideration, they are given admission and priority based on what caste (Jati) they are from. If one is an outcaste, the easier it is for them to get into a good program. If India went back to its Hindu principles of governance, it will surely rise back to the top the of the world without causing any harm or bloodshed. In some ways, Indian culture, that is Hindu culture, has already accomplished that. Yoga, vegetarianism, principle of non-violence and others have become incredibly popular around the world without any "marketing" or evangelism by Hindus. There are many people who are not Hindus who find the principles of Karma and reincarnation esoteric and have researched those topics studiously. The whole field of NDEs (Near Death Experience) has made a tremendous impact on westerners' minds on the notion of reincarnation.
It is best to leave out any discussion of caste when talking about Hinduism with non-Hindus. When devious people who want to create trouble start attacking Hindus with it, they must be given fitting replies.
Although an eye for an eye may make the world blind, I like the idea of two eyes for an eye and an entire jaw for a tooth (motto of BJP

)!
Jai Hind!