Illiteracy does not go and lodge in your genes. So it does not matter whether your past 10 generations were illiterate or not.
The so called 5000 years of oppression does not make an SC/ST or OBC inherently incapable. That is a convinient falsehood being spread around to justify an evil agenda.
In todays' world, the opportunities are available on the basis of economic status of the family. We must support reservations for economically backward. As everybody claims, most of the SC/ST and OBCs are economically backward, so even with economic status based reservation policy they are sure to get the benefits, albeit under a different name. What is the problem with that?