It's really kind of simple: when everyone in the world knows that your team can drive to the basket whenever they want but can't shoot the 3, your team gets defensed accordingly. Meaning driving lanes are blocked off and jumpshooters are left open to square up and hoist some 3s. This is going to happen to UConn all year.
The real failure is in not recruiting a pure shooter or two. You really have to have one. As prior posts alluded to, the 2013-14 team had 3 starters who shot better than 40% on 3s. That makes up for weaknesses in other areas.
It's also true, however, that in tough, tightly contested NCAA tournament games, shooting strokes often go south and defense and rebounding wins the games. And UConn could stand to improve a bit on their defense. Although I did not see it allowing a team to make 12 of its last 13 FGs is strong evidence of weak defense being played, and the defensive team being worn down. Cobb being out was one less guy to rotate and it hurts in games like this even, if as Shaggy said, he would have fouled out with 5 boards. Because his presence means others can take chances rather than save fouls.