Is caste still sustainable in an era of Universal human rights? Is caste sustainable in a democracy?

To me in India, caste (hierarchy of the pure and unpure) is not the only thing that challenges the universal human rights. The Varna system too is a form of prejudice. Racism and other forms of prejudice started early in India. The Aryans were fair-skinned nomadic fighters. They settled in India in about 1500 BCE, after conquering the original, dark-skinned inhabitants, whom they included in the Aryan society as artisans and manual workers. It was the Aryans who introduced the system of Varna, which is still an important feature of Hindu society today.
Varna is a Sanskrit word which means colour. The class divisions were based on the colour of people’s skin and were a form of racism. These divisions gave Aryan higher social standing than the darker skinned lower castes. Over the centuries there has been intermarriage between people descended from the Aryans and those descended from the original inhabitants. Many other people have also settled in India, so there is no such thing as Aryan racial purity anymore. However, the Varna system is still very strong. There is religious support for it in the Bhagavad-Gita and in the Rig Veda, book 10, Hymm 90 on how the four Varnas of the Hindu society were born:-
“When the primal man is divided
The Brahmin (priest) arose from his mouth),
The Kshatriya (warrior) from his arms,
The vaishya (merchant) from his thighs and
The Shudras (artisan) from his feet.” (Purusha hymm)
From these verses above, I could infer several things. Since the Varna system is found in both the Bhagavad-Gita and Rig Veda, it must be very old. Let’s assume it to be 5000 B.C. Given that the origin of the Varna system is from the Rig Veda, the institution itself must be divine and “word of God(s)”. The Almighty God himself divided the Hindu society into four Varnas. In the view of the fact that God did it, it must be for the good of the people and permanent in nature. In addition, seeing as the four Varnas were born from different part of the body which are in descending order, these Varnas must also have hierarchical order. The Brahmin must be at the top and Shudras at the bottom.
However such concept is often dynamic in nature. As a result, Hindu societies were faced with some problems as the society advanced. Problems such as family life had not developed sufficiently, inter-Varna marriages were increasing, incoming of foreigners into India and many more created a situation where the Varna system failed. Since these social, economic, geographical and other factors sprung up, the institution of castes were developed to tackle such problems.
So the question is whether the caste system still sustainable in an era of Universal human rights? The traditional Varna and caste system in Hindu society is gradually breaking down in large cities. However personally, it still affects the basic human rights of many Hindus, especially in the rural areas. For example the dalit or the untouchables. Mahatma Ghandi called them harijans, which means children of God, but they called themselves dalit which means oppressed. “Untouchability” was abolished by law in India in 1950s. Even so, many dalits are not free to live where they wish, as their homes are deliberately situated away from those of high caste Hindus, and in many villages they live just outside the village boundary. I think in India, Hindus are not free to marry anyone they like, since caste and family tradition still control the choice of marriage partners in most cases. I personally think although each caste normally does their traditional jobs, they are interdependent on each other and mutually accommodating. Furthermore, Hinduism is in agreement with the UN declaration of Human rights but with practice differ in India. In spite of the formal declarations of human rights, many millions of people in India do not enjoy a standard living adequate for their health, and well-being, housing, medical care, unemployment and old age. The Indian constitution itself is not based on Hindu ethics and India is a secular country. However, it affects the 83 percent of the population who are Hindu. Some of the aspects o the constitution conflicts with traditional Hindu ideas such as the right of equality, the right to property and etc but Hinduism has developed over 3500 years, in which it always adapting to the changing times. In theory, there is full acceptance by Hindus of the constitution.
Reflecting back, the origin, rise and present position of the Varna, caste system showed that it has lost almost all its relevance. It has become a liability, so much so that it wrongly gives and perpetuates a non-existing complex. The very fact that most of the people, who call themselves of a particular community or group simply because they were born in that caste, do not think, behave or work in accordance to that caste anymore. With that, caste is not sustainable in an era of Universal human rights.