I don't think they're saying that great ideas can't spread from less prestigious institutions, I think they're saying that ideas from more prestigious instituti

I don't think they're saying that great ideas can't spread from less prestigious institutions, I think they're saying that ideas from more prestigious institutions will spread further than similar ideas from less prestigious ones. We intuitively know this though, don't we? In rhetoric we even have the fallacy known as the argument from authority: https://en.wikipedia.org/wiki/Argument_from_authority https://en.wikipedia.org/wiki/Argument_from_authority The idea being that because humans are prone to operating in hierarchies we give more weight to persons and institutions that are seen as more authoritative for whatever reason, one reason being their supposed prestige. It's neat a study bears this out.