It’s not socially acceptable anywhere in the urban places but in rural places it can a quite a problem.
I have lived my entire life in a urban city without any discrimination whatsoever, but I have also heard of rural places where they would literally burn people alive for intercaste marriage.
One of the main reasons it’s not extinct yet is because people love to take “pride” in their caste. There are plenty of songs dedicated to “jatt” people, people of a higher caste. “Khatris” are often glorified in movies for fighting. You can see the problem is same as if white people started making songs on “being white and proud” and Britishers claiming victory in ww2 because they were “white”. It’s absurd and I have felt the pain but I am thankful for the present situation and I suppose it’s better than being burnt alive haha.
Yes there is reservation and that’s absurd too, imagine if “black” people were allowed reservation for jobs in government.