I have a really hard time putting much stock in metaphors that have so many components and work backwards from the metaphor to the real world. Too easy for the truth and usefulness of the advice to get stretched out to make the comment as a whole flow properly.

Uber/Airbnb/et al aren't still private just because there's some uncomfortable risk they're afraid will push away public investors. There's a whole host of reasons to stay private (lawyers, executive time/energy, SEC compliance, public investors are generally more myopic than private ones, etc, etc, etc). The "nut" you mention might be an inconvenience, but it's surely not even close to the most important reason to stay private.