Or if you mean there's more to the experience of going to college than just the coursework, of course that's true as well. But if everyone went to MIT (or any other selective school), that experience would change too; all those people would not be getting the same experience that people going to MIT now are getting.

In short, it is not really possible for everyone to "go to MIT" (or any other selective school) in either of the above senses. So I was focusing on what is possible, namely, for everyone to have access to the same actual learning materials that MIT students have access to.

There is one other thing you could be referring to that the online materials can't give you, namely in person instruction and feedback. Personally, if I think back to the classes I took at MIT, I didn't learn anything significant in those ways; everything significant I learned, as far as the actual academic material was concerned, I learned from reading the course notes and textbooks and working the problem sets and taking the exams (and seeing what I got right and what I got wrong). And all those things are available to anyone who goes to the OCW site. I can't say for sure what other people's experiences are, but I think this quote from Gibbon is relevant:

"The power of instruction is seldom of much efficacy, except in those happy dispositions where it is almost superfluous."