I agree, it seems a bit like link bait. From what I understood, though, the author's point has some merit -- in stocks, you are at least always able to cash out, to change your mind, to have new priorities. In the modern form of start-up investing, your fate becomes inextricably bound with that of the start-up, with your only options being an eventual pay-out or loss of your investment. I'm not saying I think this indicates anything about a "bubble," just that (if I understood the article correctly) there is a distinct difference between the value modern start-ups provide and the value that a public investment provides.