Larry David was the brains behind Seinfeld. It's evident in how the last couple seasons without him descended into slapstick and caricature.
Seinfeld is still god-tier. So is Curb.
The last seasons of Seinfeld are great - more absurd and out there but with some of the funniest episodes and moments of the series. Just a different thing which was in fact quite nice after many seasons.
Seinfeld will always be on top. But Curb filled the gap it left almost entirely, with a unique flavor of its own, and now we have tons of Curb episodes to go back to as well as the Seinfeld ones and maybe we'll get even more. It's just a beautiful thing all around.