It is, according to Susan Gutfreund, the society hostess, the epitome of civilized living. It is, said Karen Mordechai, an entrepreneur behind the successful dining series Sunday Suppers, in Brooklyn, a far less geeky way of networking than a Meetup. It is, said Alex Hitz, the author of a new cookbook, “My Beverly Hills Kitchen: Classic Southern Cooking With a French Twist,” the great social equalizer.

It is the dinner party. Remember those?

“The world is so changed, hardly anyone does them anymore,” said Louise Grunwald, widow of the former diplomat and Time Inc. editor in chief Henry Anatole Grunwald and among the last left standing of New York’s acknowledged great hostesses.

“It’s over,” Ms. Grunwald said, not entirely convincingly, given that invitations to her dinners remain much coveted, only partly because her kitchen turns out great food. “You may want the dinner party to come back, harkening back to another era. But it will never happen.”

There was a time, not so very long ago, when any such doomful pronouncement would have sounded far-fetched. New York, after all, has always been oversupplied with those who pride themselves on their tables, competing to populate them with lively strivers who do their social networking not on tiny, glowing screens but cheek by jowl.