It is an undeniable fact that TamBrams are smart. It is evident in places of higher learning where merit is the basis of selection, you find a number of them there. In terms of academic achievements too they are well represented, I would say overrepresented. I am not sure if the hatred towards them would have been that intense if they are not perceived as intelligent.
sravna, you may not agree with what I am about to say, and that is alright, I only request you to think about it.
There are lots of facets to human intelligence, ability to master bookish knowledge is surely one of them. The strict caste-based division of work meant there was caste-based specialization of skills. The Brahmin specialization was bookish study and they did get good at it over the centuries. Since this is all they did, they placed high value in education.
So, if what you say is true, i.e. TBs are smart, that only means they are smart in book-based education. As a result, perhaps the TBs have a leg up in the world economy that is increasingly dependent on this kind of smartness.
In a similar vein, the caste-based division of work also meant that there were castes that put less value in bookish education, but placed higher value in physical activities like carpentry, masonry, farming, etc. These castes, in general, tended to do well in these fields, and one could say they are very smart in those respective fields and the TBs are in general quite daft in those fields.
BTW, this caste-based division of work is not a very efficient system. It can only let the best talents within a caste to shine in the field of that caste, not the best talent across all.
Let me end with a story, a parable of sorts, I am sure many would have already heard it.
There was this very learned Brahmin scholar who wanted to cross a mighty river. He hired a boatman. As the boatman was rowing, this scholar quizzed him about what he has studied, whether he has studied this shastra or that shastra. The boatmen being an illiterate answered no to all these questions. The scholar then lamented that the boatman has wasted his lifetime without any education.
After a little while, the boatman asked the scholar whether he knew how to swim. The scholar answered no. The boatman laughed and said to the scholar, "it looks like you are the one who has wasted your lifetime without learning how to swim, there is sudden increase in river current, I am unable to control the boat, and it looks like it is going to capsize any minute."
You may be right sravna, TBs may be quite smart, I don't know, but, IMO that is not that important. What is important, I think, is to be able to get along with people, use whatever smarts we have in whatever field it may be, and contribute to the welfare of the community in which we live.
Cheers!