Seinfeld is what it is, and those who find it boring must find their own lives incredibly so. This show isn't reality for sure, it's almost a parody of reality that really makes you think about the little things like the odd quirks people have, relationship dynamics, and habits that never really die.
Seinfeld is a show where four not-very-likable characters get themselves into difficult situations, usually dragging along a cohort or two. There is very little action, and nearly all the comedy is either subtle or slapstick. None of the cheap shots or frat boy humor you see in the lazy comedies and sitcoms of today. To be clear - Seinfeld was only around when I was a child, it really isn't a contemporary show for me. I didn't start watching it until I was old enough to appreciated the layers of comedy that Curb Your Enthusiasm's Larry David built for each character. Now I look back on it fondly as I avoid already dried up newcomers like 2 Broke Girls and Whitney.
So, if you enjoy everyday hilarity, memorable lines and well-developed characters with real flaws and nearly real lives, Seinfeld is probably for you.