These aren't the disadvantages of an elite education, it's the disadvantages of not having sufficient breadth of experiences with people from a sufficient breadth of social-economic backgrounds. Get your kids to do extracurriculars where they'll meet kids from lower-income households. It'll make them able to relate to them and understand them better.
Yup. I go to an ivy and many of my best friends are construction workers or service workers who will likely never attend college. It's because I wasn't sheltered (nor particularly wealthy as a kid). And when you're there, talk to people. Not just ones who will help you climb the social ladder in whatever elite clubs and orgs you want to join. People of all stripes. It's a much more diverse group in every way than the…
I spent my 20s working in STEM and living in between MIT and Harvard which meant that a large portion of my social circle was drawn from those schools. I see where both sides are coming from here. On one hand you're right in that there were also plenty of people in our circle who came from very different backgrounds. By and large these were normal people and not the sort of socially awkward weirdos the article describes.
On the other hand the article rings true at times. The bit about worrying about their occupation due to the 20 year reunion, I heard that exact thing countless times. The lack of recognition of the second chances to succeed or that they have a ridiculous social network that others do not was also a big thing. And through it all there was always a certain baseline, well, elitism. It was almost never direct but it was always there. It wouldn't be directed at the rest of us but you'd hear it amongst themselves, "I can't believe a Harvard graduate is doing that" when "that" is something that their good friend also does. That sort of thing.