In terms of the content that's taught during an undergrad degree, in the sciences it largely follows the same textbooks everywhere and those textbooks were written decades ago. You tend to get more advanced courses towards the later years which might be more modern and these might differ more substantially between institutions, but again you could get the same knowledge by reading textbooks anyone can buy. So no, the material is not really different and you could definitely get the same level of knowledge by teaching yourself (and if you're motivated enough to teach yourself you'll probably be better than the majority of those ivy league grads by the end of it).
However, anyone attending an elite university could have attended a non-elite university, and if you are given the choice you should almost invariably choose the elite university. I can write more about the upsides if you want, I don't feel like it right now, but to condense matters it comes down to the signalling value, surrounding yourself with successful people, access to greater resources on many levels.
