Caste system is not that simple for example Jats are under reservation in one state but considered upper caste in adjacent state and gets no reservation.
Yes Reservation is still needed. India is big and people who got oppressed under colonial rule would take a few generations more to come up.
Bigger issue is exploitation of caste lines for politics.
Given that 90% of people from India in SWE seem to be from higher caste (I don't really know the exact statistic but it is something like that), then it seems like the reservation is still needed.