Well, the BCCI hosts the tournament with so much fanfare and cities rejoicing when you win it. Like it or not, It's the biggest thing in cricket right now, except for a few series rivalries like Ind vs AUS or Ind vs Pak.
It maybe a non entity for you, but
Anver's point is relevant. T20 is a big event for India for the cricket supporting publicand it doesn't become unimportant suddenly, definitely not to the extent of true fans knowing what real cricket is. They lap it up like anything.
If we had made it to the semi finals at Pak's expense, most of us lot will be taunting Pak/SA
(Although not with a suck it Pakis I hope)