One thing you should always keep in mind and that is reservation is always helpful for people availing it and is not beneficial for general candidates here in this case you are getting confused because general closing rank is about 32892 in the course you stated while for obc the cutoff is 7542 in the obc category rank and obc category rank of 7542 is much greater than general rank of 32892 greater means that general rank of  32892 is better hence obc quota is beneficial.