We can't ignore the age range for each league. 16-20 for CHL while it is 18-23 for NCAA. Massive difference. And yes, the more JR/SR a NCAA team has, they won't be as talented as the kids who left after FR/SO years, but like any league, there are kids who are great in that league, but are not going to advance or do better up another level.
So, it's not an apples to apples comparison. BCHL, USHL, CHL are basically the same age range at 16-20. NCAA is a mix at 18-23 as AHL clubs can do as low as 18, but more than likely their youngest players at CHL graduates at age 20 onwards.
CHL kids should leave for NCAA for that reason. Going from being in the 19-20 age group to being among the youngest ones as a teen in NCAA vs young 20 somethings. Plus, a huge factor in their decision is the money that NCAA pumps into the coaching, travel (plane), support staff (nutritionist, trainers, skills coaches), and facilities. Most AHL teams couldn't compete against that either.