That is like saying, people who self-select to go to the physics department go there only to be with other physics students are and that it, "doesn't have anything to do with the teachers, [or] the curriculum."

What is more likely, is the school does an excellent job affording students the opportunity found successful, venture-backed companies. Similar to the way the Physics professors and curriculum afford physicists the ability to be good at physics.

The fact the article highlights this opportunity for other entrepreneurially minded people, who may want to attend in the future, is exactly what the data in the article is supposed to do.

I don't agree, I think it's more likely than not that a school specifically designed to foster a particular type of thinking is at least somewhat more effective at it than others. Just like Stanford is likely more effective at developing elite researchers.

I don't think there's nearly enough information to determine that confidently, but we're simply talking about beliefs at this point.