This shows that coaching helps.
Yep, exactly. Look at teams like Davidson too, when they almost went to the Final Four. Besides Curry, they didn't really have anyone who was GOOD. Their PG was pretty good, Richards, but nothing spectacular. When you face very good teams, such as Kansas, you need more than just one amazing player to win. They didn't have that, but they were well coached and they almost made the Final 4.
Coaching in NCAA matters a ton because 99% of these players will NEVER even put on an NBA uniform. The NBA, coaching might not matter as much because the guys are so good, every single one of them is almost automatic in some fashion.
In college? Not so much..this is where coaching comes in. You can't expect to acquire five amazing parts of a watch that when put together randomly they magically work amazingly well. You have to put them together perfectly well. Just like with players, just because you have five amazing guys doesn't mean you're going to be amazing and just because you have five unheard of guys doesn't mean they're going to suck. It's all about coaching..