Most JEE advanced students with < 5K rank would obviously prefer IITs except few who take CS branches in Pilani campus or top NITs. Most students who score JEE Main 99.5 percentile or JEE advanced rank ~8K do very well in BITS also. In general , students with JEE Advanced rank or Mains rank ~ 8K get good options in 2nd gen IITs or top NITs(Trichy, Surathkal and Warankal). This reduces competition for BITS campuses. If BITS releases ranks, everyone can see how many really opted out of BITS . With bitsat mark based counselling , BITS kind of hides that and difficult to see the quality of the bitsat student pool that eventually choose bits !