The main fields of human endeavor will be culture, arts, sciences, creativity, philosophy, experimentation, exploration, and adventure.
...it's like he's never met anyone who didn't attend a top tier university. Here's reality:
The main fields of human endeavor will be copulating, hustling, consuming low-brow entertainment, eating, and the occasional lunatic running amok.
...and honestly, we're square on that path right now. There are huge numbers of people who are literally useless eaters. Go to a Wal-mart supercenter sometime. Huge big fat people buying candy, soda, potato chips, frozen meals--often paid by the public dole. I'm not even complaining. Unless you start a sterilization program (and we aren't) it's the unavoidable present and future.
There are many people who 'endeavor' exactly the way he describes, many more than I always wanted to believe. And many of them are quite intelligent, so it's not just about IQ.
While changing our approaches to education and the right motivation, in my opinion, can bring people much further than some of us are inclined to believe, this is a limited solution for all the grownups who live in the way OP describes.
Granted, you could remove that profitability floor with universal basic income.
These elite IQ guys like Andreesen in coastal bubbles are totally out of touch with broader society. They really don't grasp that a huge fraction of the population is not going to be training up for the services and digital economy, because that's not realistically possible.