he would fail miserably at starting a company because he equates the product/service his company would make/offer with his education
I think you misunderstood the post. The author said nothing about how his PhD would directly relate to starting a new company (the author's research is theoretical, anyway). Rather, the point is that by acquiring a valuable skill (a PhD from MIT), his risk profile is lower: he could go and start a new venture, or equivalently wager all his assets at the roulette table; either way, his skills mean he would be able to find a good job if the gamble doesn't turn out well.
If you like, substitute "MIT PhD" for "become one of the top 5 Linux kernel developers" for an equivalently rare, valuable skill that would help to ensure future employment.
Upon rereading, I agree with your assessment, but the crux of the issue is that his example of Lisa isn't so "pristine."
He argues that her small business failed because her skills weren't rare and valuable. Then he says his skills are rare and valuable.
A consistent argument springing from those two statements would be either a) my business won't fail because my skills are rare and valuable, or b) Lisa can't find another job in marketing (the job she held for a decade before quitting) because those skills aren't rare and valuable.
He didn't make either of those arguments, instead focusing on her yoga instructor skills. It makes for a muddled post.
I think you misunderstood the post. The author said nothing about how his PhD would directly relate to starting a new company (the author's research is theoretical, anyway). Rather, the point is that by acquiring a valuable skill (a PhD from MIT), his risk profile is lower: he could go and start a new venture, or equivalently wager all his assets at the roulette table; either way, his skills mean he would be able to find a good job if the gamble doesn't turn out well.
If you like, substitute "MIT PhD" for "become one of the top 5 Linux kernel developers" for an equivalently rare, valuable skill that would help to ensure future employment.