I saw that, and was 50-50 if he was referencing JFK Jr. explicitly.
On one hand, Greenspun is a pretty noted Libertarian and not a fan of the Kennedys. On the other, he often references flying to Martha's Vineyard for day trips in his other writings about aviation, and it seems like a pretty sensible place to fly to if you're into civil aviation and looking for a day flight somewhere from Boston (where I believe he's based).