I don't know. We're not talking windfalls of financial success here necessarily.
I'd expect Harvard or a similar institution to be mostly full of the esoteric: people with an intense focus of study on something we've never heard of like some biological property of a specific type of plant or some 500 year old historical event that you have to travel to a national archive and learn a dead language to read about.
Ideally those people should be able to come from most economic and status backgrounds.
I would imagine there's a lot of overlap between those two groups
In fact I think it impossible to be part of the former without being part of the latter