There was a time when — even in America divided — there were certain shared cultural experiences. Everyone knew what guest made which joke or gaffe while sitting on the couch next to Johnny Carson. Most could easily keep track of which Huxtable/Cosby kid was in the good graces or the dog house with papa Cliff/Bill. On Ed Sullivan’s variety roundup, ballet dancers, jugglers and singers from the Beatles to the Supremes divvied up the hour. These pop culture moments have become fewer and fewer as viewers have split into small, dedicated slivers in the cable and online universe. Now a hit is declared with audience numbers that would have made the networks tremble.

It’s no wonder that the 25th anniversary of the television show “Seinfeld” is being treated with such pomp and relative reverence. It harkens to a time in the not long ago 1990s when even a final episode judged mediocre could mean ratings gold.

The cast of "Seinfeld." (Courtesy of NBC.) The cast of “Seinfeld.” (Courtesy of NBC.)

But much like a typical “Seinfeld,” all is not what it seems to be — it never was. When the show, after a rocky start, hit its stride and No. 1 in the ratings, it was never as popular among all members of its potential audience.

At the time when the show was at its most buzz-worthy, it never ranked higher than 80-something in the list of shows most watched by African Americans. Ad agencies trying to hit target audiences studied such things, which revealed “Living Single” and “New York Undercover” topping a separate chart.

Differences were also found along other lines — white vs. Hispanic, Native American or Asian American viewers, as well between male and female viewers. In 1996, Doug Alligood, the senior vice president at BBDO who conducted the study, said in a Baltimore Sun story: “It is true, there is no public. There are instead many publics.”

For me, “Seinfeld” was less “must see TV,” as NBC branded its hits in the 1990s, than “take it or leave it TV,” and in truth I had the same attitude toward shows that surveys showed were popular among African Americans. I suppose I was never one of those faithful television viewers. But I understood the disconnect the surveys revealed, and some of the reasons why the shows “ER” and “Monday Night Football” hit the sweet spot for every group.

“Seinfeld,” like “Friends” during and after it, was criticized for its view of a New York City a lot more homogeneous than the real-life metropolis. That was the creative choice of its creators, which was fine. But it certainly made sense that those looking for a familiar face or any sense of authenticity would switch channels. The minorities that passed through the show — the slick lawyer Jackie Chiles, played by Phil Morris, or a guest spot by Seinfeld’s friend, comedian George Wallace — stood out in part because of the rarity of the occasion.

Humor, of course, is subjective and personal — a lot of folks of every race and age group didn’t particularly warm up to Jerry and friends. Yet the celebration of “Seinfeld” as a show that everyone loved and mimicked isn’t strictly true. In fact, the current festivities pointedly paper over some of the cultural conflicts that have since embroiled the Seinfeld cast and ruined the “one big family” fantasy.

There were Jerry Seinfeld’s comments when asked about diversity in his Web series “Comedians in Cars Getting Coffee” in an interview with BuzzFeed on “CBS This Morning” earlier this year. “People think it’s the census or something,” he said. “This has gotta represent the actual pie chart of America? Who cares? Funny is the world that I live in. You’re funny, I’m interested. You’re not funny, I’m not interested. I have no interest in gender or race or anything like that.”

While those comments caused a minor controversy, it was the 2006 racial rant by Michael Richards that led many to see the show’s Kramer in a very different light. The flame-out of Richards, whose response to an African American comedy club heckler descended from insult to racist harangue, complete with lynching imagery, was shared widely on the Internet, and his career has never been the same.

It’s not just the TV landscape that has changed since the 1990s but the increasing recognition of America’s diversity. The sought-after youthful and shifting demographic means Hollywood is readying a fall television season with more people of color in lead roles. Hit maker Shonda Rhimes, of “Grey’s Anatomy” and “Scandal” fame, is taking over the programming of ABC’s Thursday night lineup.

Looking at “Seinfeld,” 25 years after the fact, it’s clear it earned, if not universal devotion, a spot in TV history. For a while there, you couldn’t pick up a magazine cover without seeing its cast looking back at you. In 2014, it all seems as much relic as touchstone.