You couldn’t do that finale for Friends or The Office because the relationships between the main characters became such a huge part of the show. You have to tie up the storylines
But Seinfeld was never realistic or life-like— the characters stayed caricatures the whole way through. It was never about love interests or family bonds or any kind of progress. A true sitcom—Put a couple zany characters in a humorous situation and see what happens. And the finale is like the ultimate example of that. Four friends have every weirdo they’ve ever met come to a trial to attest to every bad thing they’ve ever done. Who would even think of that??
To be fair, I never watched Seinfeld live so I may have felt different about the finale if I had