See report here:

http://dailyentertainmentnews.com/breaking-news/dan-goldstein-lawyer-chased-down-ivanka-trump-in-flight/

'Goldstein’s full name is Daniel Jennings Goldstein, he is a wealthy Jewish lawyer who currently resides in Brooklyn. He is a homosexual man who was traveling with his husband [Matthew Lasner, a professor at Hunter College] and child [a boy, Amos].'

I find it very difficult to understand what purpose could be accomplished by hassling someone simply because of who her father is.

He sounds like the sort of man who might feel threatened by Pizzagate; it's pretty clear from this incident that he is more than normally agitated about what a Trump presidency might mean. Wouldn't you have to feel personally threatened before indulging in this kind of thing? (I'd give anything to see his Instagram!)