Other professional goals, skills, or structure-based needs might be satisfied by college,

As you pointed out earlier in your response, Internet learning (and LW in particular) could have been particularly useful before attending college. I would go one step further and suggest that attending college and learning from the internet should not be mutually exclusive for those who are interesting in learning and making a potential college social life trade-off.

I currently believe that most students attending college realize that the degree itself is of primary signalling importance, even if they're not able to explicitly articulate why.