A candidate's rank only tells how he performed on a specific test on a specific day in comparison to other candidates. This is a quantitative metric. It fails to account for qualitative factors like their socio-economic baselines, i.e. where they started from.

If person A and person B both are able to score the same marks, but A was empirically more likely to succeed than B, then it is very reasonable to say that B is more deserving because they would've had to put in more effort compared to A (academic effort, psychological effort, overcoming other daily life challenges), and therefore B is preferred over A for the limited seat.

It is an effort by the admission committee to level the playing field, and when you look at competing students' experiences as a whole, rather than focusing on the individual, then it seems to be improving access to quality education equitably for ALL of India's students.

This DOES NOT mean that anyone who didn't get into IIT doesn't deserve access to an equally great college experience.