I don’t think IIT Kanpur has lost its charm considering its excellent research facilities and the research work it has done in recent times. Also, the excellent placements testify to its charm and credibility. But if you are talking about attracting top rankers, then yes, IIT Kanpur is a little behind IIT Delhi and IIT Bombay in attracting the top 100 JEE rankers. There are many reasons why this is happening
All in all, IIT Kanpur hasn’t lost its charm even a bit and is still known for its cutting-edge research and excellent quality of education.