Is celebration of ‘Seinfeld’ as cultural touchstone just wishful thinking?

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.

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.