As a graduate of a Non-Ivy and an Ivy League school, I can tell you the differences are significant.
I went to a private non-Ivy school (Syracuse) for my undergrad degree (Physics & EE) and when I went to the Ivy League (Cornell) school for graduate work, I can tell you the differences in intellect and capacities were startling. The Ivy kids were much smarter than my peers at Syracuse. But this was 20 years ago. I would imagine much has changed.
I’m not arguing what you are purporting. I would imagine that the average intelligence level at Cornell is much higher than at your basic state school. My argument was unless you are going to be on Wall Street, or at some big law firm or going for the top of Goldman Sachs, what’s the point? If you are like the millions of us who get a degree and work good high paying white collar jobs, the lack of an ivy league degree will not bar your entry into the workforce.