NBA - Main

I had no idea just how popular college basketball is. For example, the subreddit has 2.2M subscribers. Although here it has 8.5M, it's really absurd how popular college basketball is. What's so special about it compared to NBA? I mean only Americans can really watch it. While in the NBA, it's more global. I've even heard that the revenue generated for unpaid college basketball players is extremely high, some even higher than certain NBA franchises.

Why is college basketball so popular? What makes this so special if those players are not proven to be in the NBA yet? On the other hand, college baseball isn't really popular compared to MLB itself.